Solve the equations below. Give exact solutions only. Show your work.

a) 5x^2 - 7 = 72
b) x(x + 2) = 5
c) 3x^2 + 2x - 4 = 0

Please help!

Answers

Answer 1

Step-by-step explanation:

remember, the general formula to solve a quadratic equation ax² + bx + c = 0 is

x = (-b ± sqrt(b² - 4ac))/(2a)

a)

I think there is a typo, and this should be

5x² - 7x = 72

5x² -7x - 72 = 0

x = (7 ± sqrt(49 - -1440))/10 = (7 ± sqrt(1489))/10

x1 = (7 + sqrt(1489))/10

x2 = (7 - sqrt(1489))/10

b)

x(x + 2) = 5

x² + 2x - 5 = 0

x = (-2 ± sqrt(4 - -20))/2 = (-2 ± sqrt(24))/2 =

= (-2 ± sqrt(4×6))/2 = (-2 ± 2×sqrt(6))/2 =

= -1 ± sqrt(6)

x1 = -1 + sqrt(6)

x2 = -1 - sqrt(6)

c)

3x² + 2x - 4 = 0

x = (-2 ± sqrt(4 - -48))/6 = (-2 ± sqrt(52))/6 =

= (-2 ± sqrt(4×13))/6 = (-2 ± 2×sqrt(13))/6 =

= (-1 ± sqrt(13))/3

x1 = (-1 + sqrt(13))/3

x2 = (-1 - sqrt(13))/3


Related Questions

Plssssss help! I'm timed

Which represents a quadratic function?
A: f(x) = 2x3 + 2x2 – 4
B: f(x) = –7x2 – x + 2
C: f(x) = –3x + 2
D: f(x) = 0x2 + 3x – 3

Answers

Answer:

B: f(x) = –7x2 – x + 2

Step-by-step explanation:

The biggest exponent in a quadratic function is a 2.

A. Is NOT the answer because it has an exponent of 3 (that's a cubic not a quadratic)

C. Is NOT the answer because it is linear, if you graph it, it's a line. The highest exponent is 1.

D. Is NOT the answer, because even though it shows a power of 2, the coefficient (the number next to it) is a zero, so that term would fall out of the equation and it would be linear like C.

So B: f(x) = –7x2 – x + 2 is your answer. Its highest exponent is two and if you graph it, it would make a parabola.

add (7x^2-3 x)+(5x-6)

Answers

Answer:

Step-by-step explanation:

(

4

x

)<(

15

5(5x−2)−3(7x−3)

)

(

4

x

)<(

15

25x−10−21x+9

)

(

4

x

)<(

15

4x−1

)

15x<16x−4

4<x

∴x∈(4,∞)

Gas grills are on sale 20% off. The sale price of the grill that I like is $399.20. What was the original price of the grill?

Answers

Answer:

499

Ste-by-step explanation

80 percent of the original price is left.

If you divide by 4 you get 99.8 which is 20% of the original price. Then if you multiply 99.8 by 5 you will get 100% of the original price which is 499

You can also do 399.2 * 1.25 = 499

The figure below shows a quadrilateral ABCD. Sides AB and DC are congruent and parallel:

(image)

Which statement best describes a flaw in the student's proof?

Angle DBC and angle BDA form a pair of vertical angles, not a pair of alternate interior angles, which are congruent.

Triangles ABD and CDB are congruent by the SAS postulate instead of the SSS postulate.

Triangles ABD and BCD are congruent by the AAS postulate instead of the SSS postulate.

Angle DBC and angle BDA form a pair of corresponding angles, not a pair of alternate interior angles, which are congruent.

Answers

The statement that best describes a flaw in the students' proof is;

Option D; Angle DBC and angle BDA form a pair of corresponding angles, not a pair of alternate interior angles, which are congruent.

From the given image, we can see that;

AB ≅ DC

Let us analyze each given option;

A) ∠DBC and ∠BDA are in the same triangle ΔBDC. Now, they can't be a pair of vertical angles because vertical angles are a pair of opposite angles formed when two lines intersect but this is not the case here.

They are also not alternate interior angles because alternate angles are formed when a transverse line intersects two coplanar lines and again that is not the case here.

B) In ΔABD and ΔBDC, we see that;

AB = DC. Also, by theorem of alternate interior angles, we can tell that;

∠ABD = ∠BDC

Similarly, ∠BDA = ∠DBC from alternate interior angles.

Thus, there is one corresponding side and two non-included angles which means the triangles are congruent by AAS Congruency postulate.

C) As seen in B above, this statement is correct because the triangles are congruent by AAS postulate.

D) Corresponding angles lie on the same side of the transversal.  In this case, ∠BDA and ∠DBC lie on opposite sides and are even congruent by alternate interior angles.

Read more about congruency at; https://brainly.com/question/7727792

Which expression is equivalent to -16 - 7?

A. -16 + 7
B. -16 + (-7)
C. 16 + (-7)
D. 16 + 7

Answers

Step-by-step explanation:

B. -16 + (-7) ...this is the same as -16-7

5+(3²-4)-6/3 please help

Answers

Answer:8 is the answer.Step-by-step explanation:5 + (3² - 4) - 6/3=> 5 + (9 - 4) - 6/3=> 5 + 5 - 6/3=> 5 + 5 - 2=> 8Conclusion:

Therefore, 8 is the answer.

Hoped this helped.

[tex]BrainiacUser1357[/tex]

what would be the linear equation for (0,2) and (4,-4)

Answers

Answer:your mom

Step-by-step explanation:

srry had to do it

5+6b+3d how many terms are in the expression

Answers

Answer:

3

Step-by-step explanation:

5 is a term 6b is a term 3d is a term

Rachael is placing a protective cover on a glass case. The case is a cube, and the perimeter of one cube face is 56 inches.

How many square inches of the protective covering does she need for the case?

Answers

Answer:

336

Step-by-step explanation:

We know that a cube has 6 faces which means we can use this equation:

56 x 6 = 336

336 square inches is the answer.

Perimeter=56in

Side=56)4=14in

So area of one side=

(side)^2=(14)^2=196in^2

Cube has 6sides

So total protection:-

6(196)1176in^2


Factor each polynomial completely.
b) 5x6 - 25x5 + 30x4
+

Answers

Answer:

10x+5

Step-by-step explanation:

You add or subtract 5x by -25x by 30x to get 10x. However, then you add 6-5+4 which is 5.

Answer:

5[tex]x^{4}[/tex] (x - 3)(x - 2)

Step-by-step explanation:

5[tex]x^{6}[/tex] - 25[tex]x^{5}[/tex] + 30[tex]x^{4}[/tex] ← factor out 5[tex]x^{4}[/tex] from each term

= 5[tex]x^{4}[/tex] (x² - 5x + 6) ← factor the quadratic

Consider the factors of the constant term (+ 6) which sum to give the coefficient of the x- term (- 5)

The factors are - 3 and - 2 , then

x² - 5x + 6 = (x - 3)(x - 2)

Then

5[tex]x^{6}[/tex] - 25[tex]x^{5}[/tex] + 30[tex]x^{4}[/tex] = 5[tex]x^{4}[/tex] (x - 3)(x - 2) ← in factored form

What is the factored form of n^3+512 (please answer) picture provided

Answers

[tex] {n}^{3} + 512 \\ = {(n)}^{3} + {(8)}^{3} \\ by \: using \: {a}^{3} + {b}^{3} = (a + b)( {a}^{2} - ab + {b}^{2}) we \: \: \: get \\ = (n + 8)( {(n)}^{2} - n \times 8 + {(8)}^{2} ) \\ = (n + 8)( {n}^{2} - 8n + 64)[/tex]

Hope you could get an idea from here.

Doubt clarification - use comment section.

Ajay is going to invest his money into 2 different stocks. Both stocks are independent, and each stock has a 50%
chance of being successful and a 50% chance of failing.
Each stock will make Ajay $500 if it succeeds or lose him $500 if it fails.
If X is a random variable that represents Ajay's profit from investing in these 2 stocks, drag the bars to graph
the probability distribution for all possible values of X.

Answers

The bar graph represents the value of Profit (X) for the different probabilities of stocks x and y.

It can be drawn as follows.

Let x and y denote the two stocks .

The probability of success of x is p=50%= 50/100=1/2 = 0.5

The probability of failure of x is q= 50%= 50/100= 1/2= 0.5

Similarly

The probability of success of y is p=50%= 50/100=1/2 = 0.5

The probability of failure of y is q= 50%= 50/100= 1/2= 0.5

Then their joint distribution can be calculated from the following table.

        x              0.5               0.5               h(y)

y

0.5                  0.25            0.25              0.5

0.5                  0.25             0.25             0.5

g(x)                 0.5                 0.5               1.0

It is evident from the data that x and y have the same probability at each point  when both x and y are at

successfailuresuccess and failurefailure and success

But the random variable X will have different values for

both success  = $500+ $500= $ 1000 both failure  = -$500+ -$500= $- 1000success and failure = $500+ $-500= $0failure and success = $-500+ $500= $ 0

For the bar graph click

https://brainly.com/question/25196929

https://brainly.com/question/25718527

The bar graph will appear as follows.

Answer:

Step-by-step explanation:

Please help. Due Today

Answers

Answer:

Blank 1) 1 pound of raisins

Blank 2) 2.25 pounds of raisins

Blank 3) 1.2 pounds of almonds

Blank4) 1.4 pounds of almonds

find the quadratic equation of -9+3p2=-12

Answers

Answer:

How to solve your problem-  

9 + 3 2 = − 1 2

Step-by-step explanation:

− 9 +  3  2  =  − 1 2

9+3p2=-12

3 2  − 9 =  − 1 2

HELP PLEASE! Which function had the higher average rate of change between the beginning of January and the middle of March? What does this mean about the temperature in the two cities?

Answers

Answer:

Minneapolis

Step-by-step explanation:

What is the volume of a cone with the height of 6 inches and the diameter of 4 inches?
A) 25.20in3
B) 25.12in3
C) 26in3
D) 25in3
Will get brainliest

Answers

A is the answer because I had the answer on I ready

someone please help me i swear i'll give brainliest

Answers

I think this is right.

A ___ equation is a second-degree equation of the form ax^2+bx+c=0 where a ≠ 0​

Answers

Answer:

A quadratic equation is second degree equation with the standard form ax^2+bx+c=0 as the highest power is 2.

__________________.

expand and simplify 2(8x + 4y - 10)

[tex]2(8x + \\4y - 10)[/tex]

Answers

You multiply 2 by the 8x to get 16x then multiply the 4y by 2 to get 8y and lastly multiply -10 by 2 to get -20 then put it all together to get= 16x + 8y - 20
16x+8y-20 bc 8x2 is 16 so 16x; 4x2 is 8 so 8y; 10x2 is 20 so 20 and when you add the sings to it is would equal 16x+8y-20

Which of the following statements is the only
sentence that is error-free?

Answers

I don’t really know what the answer is

Can someone help me ? :

Answers

Answer:

[tex]\huge\boxed{\sf y = 100.4}[/tex]

Step-by-step explanation:

Given equation is:

53 = y - 47.4

Add 47.4 to both sides

53 + 47.4 = y

100.4 = y

OR

y = 100.4

[tex]\rule[225]{225}{2}[/tex]

Hope this helped!

~AH1807

Hello there!

Question:-

[tex]\sf \longmapsto53=y - 47.4[/tex]

This is a equation. We need to find the value of variable y.

Solution:-

[tex]\sf \longmapsto53=y- 47.4[/tex]

To Solve further,we need to overturn the equation.

That is :-

[tex]\sf \longmapsto \: y - 47.4 = 53[/tex]

Then, Add +47.4 to two sides:-

[tex]\sf \longmapsto \: y - 47.4 + 47.4 = 53 + 47.4[/tex]

On Simplification:-

Note that (-) and (+) equals to (-). So it would be 47.4 - 47.4 . Which results to 0.

[tex]\sf \longmapsto \: y - 0 = 100.4[/tex]

[tex]\sf \longmapsto \: y = 100.4( Ans.)[/tex]

Answer as a mixed fraction:-

[tex]\sf \longmapsto 100\dfrac{2}{5}[/tex]

Answer as a fraction:-

[tex]\sf\longmapsto 502/5[/tex]

______________________________________

Henceforth, the value of y is :-

[tex]\bf \: y = 100.4[/tex]

Or as a mixed fraction:-

[tex]\bf y = 100\dfrac{2}{5}[/tex]

Or as a fraction:-

[tex]\bf y = 502/5[/tex]

________________________________

I hope this helps!

Please let me know if you have any questions.

Determine whether it is possible to form a triangle
with side lengths 5, 7, and 8.
O yes
no

Answers

Answer:

YES

Step-by-step explanation:

solve the equation 3÷7x-1+1÷x=0​

Answers

Answer: The answer is 3x^2 - 7x + 7 = 0.

Need help fast on hs geometry please

Answers

Here, the two angles are equal.So, it is an isosceles triangle.So, the two opposite sides to the equal angles will be equal.Therefore, XY = YZ

[tex]\begin{gathered}15 = 4x + 3 \\ = > 4x = 15 - 3 \\ = > 4x = 12 \\ = > x = 3\end{gathered}

15=4x+3

=>4x=15−3

=>4x=12

=>x=3[/tex]

Therefore, YZ = 4x + 3 = 4(3) + 3 = 12 + 3 = 15

Answers:

3, 15

Hope you could get an idea from here.

Doubt clarification - use comment section.

the ps/ms soccor team purchased uniforms and equipment for a total cost of 692. the equiptment cost 422 and the uniforms cost 30 each. how many unifroms were ordered

Answers

Answer:

The answer is 9 uniforms.

Step-by-step explanation:

You can set up the equation like this

Total Cost = Total Cost of Equipment + Total Cost of Uniforms

So the equation would be:

692 = 422 + 30 * (# of Uniforms)

So minus both sides by 422 and you get

692-422 = 30 * (# of Uniforms)

270 = 30 * (# of Uniforms)

Then divide both sides by 30 and you get

9 = # of Uniforms

So therefore, the answer is 9 Uniforms

x=4y,2x+y=18 solve by substitution show all work

Answers

Here is the math, did it on paper, sorry it’s blue. just add parenthesis around the x in the second equation and add what x equals. then solve as PEMDAS.

What is the equation of the line in slope-intercept form?

Line on a coordinate plane. The line runs through points begin ordered pair negative 5 comma 0 end ordered pair and begin ordered pair 0 comma 3 end ordered pair.

Enter your answer in the boxes.

y =
x +

Answers

Step-by-step explanation:

Use the slope formula

Taking two points on the line:

(0,3) and (-5,0)

3-0/0+5

You will get: 3/5 as your slope

The y-intercept is (0,3)

Therefore:

y = 3/5x + 3

Q.The total surface area of a cylinder is
3080cm² and height is 21cm. Find its base radius.
Show full process.

Answers

Answer:

r≈14cm

h Height

21

cm

A Surface area

3080

cm²

Using the formula

A=2πrh+2πr2

Solving forr

r=1

2h2+2A

π﹣h

2=1

2·212+2·3080

π﹣21

2≈14.00402cm

H.E.L.P 100 POINTS!!! Match the addition and subtraction problems to their solutions: (See the picture)

Answers

Here you go,Please give Points.

A boat can travel 120 kilometers on 60 liters of gas. How far can it travel on 197 liters

Answers

Answer:

394 km

Step-by-step explanation:

197 is 197/60 times as much as 60

so the distance is also that much more: 120 km * 197/60 = 394

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