PLEASE HELP ME
Solve 2x^2-x>15
Show your work
Answers
Answer:
x < -5/2 or 3 < x
Step-by-step explanation:
Subtracting 15 puts the relation into a more standard form:
2x^2 -x -15 > 0
(2x +5)(x -3) > 0 . . . . . factor
The zeros of these factors are x = -5/2 and x = 3.
For values of x between those values (-5/2 ≤ x ≤ 3), the product of these factors will be negative or zero. In order for the product to be positive, x must not be in that range.
The solution is ...
x < -5/2 or 3 < x
_____
Additional comment
Several methods are taught for factoring a quadratic expression. One of my favorite is using a graphing calculator to find the zeros. If p is a zero, then (x-p) is a factor.
Another way to approach the factoring of ax^2 +bx +c is to find factor pairs of the product (ac) that have a total of b. Here, that means finding factors of 2(-15) = -30 that have a sum of -1. Consider ...
-30 = (1)(-30) = 2(-15) = 3(-10) = 5(-6)
The sums of these pairs are -29, -13, -7, -1. With the values 5 and -6, you can rewrite the quadratic expression as 2x^2 +5x -6x -15. This can be factored by grouping pairs of terms:
x(2x +5) -3(2x +5)
(2x +5)(x -3) . . . . . . . the factorization we show above.
__
You can see on the graph that the quadratic is greater than 0 when x < -2.5 or x > 3.
Related Questions
A medication with an initial concentration of 1. 5 milligrams per liter is administered to a
patient, and the decay rate of the drug is 10% per hour. Which equation can be used to model
the concentration, C, of the drug in the patient’s body as a function of time, t, in hours since the
drug was administered?
Answers
Answer: Exponential decay model:
y
=
x
(
1
−
r
)
t
, half life of tablet is about
2
hours and after
t
=
3
hours , remaining drug on patient's system is
42.875
mg.
Step-by-step explanation: Initial drug
x
=
125
mg ; rate of decay
r
=
30
100
=
0.3
gm/hour
Exponential model:
y
=
x
(
1
−
r
)
t
=
125
(
1
−
0.3
)
t
=
125
⋅
0.7
t
Half life:
y
=
125
2
=
62.5
mg
∴
62.5
=
125
⋅
0.7
t
or
0.7
t
=
1
2
. Taking logarithm on both sides we get ,
t
log
(
0.7
)
=
log
(
0.5
)
∴
t
=
log
(
0.5
)
log
(
0.7
)
≈
1.94
(
2
d
p
)
hour
The half life of tablet is about
2
hours.
After
t
=
3
hours , remaining drug on patient's system is
y
=
125
⋅
0.7
t
=
125
⋅
0.7
3
=
42.875
mg [Ans]
Find x, given the slope is -2. (x,-6) (-6,10)
Answers
Answer:
x= 2
Step-by-step explanation:
[tex]\boxed{slope = \frac{y _{1} - y_2}{x_1 - x_2} }[/tex]
Substitute known values into the formula:
[tex] - 2 = \frac{ - 6 - 10}{x - ( - 6)} [/tex]
[tex] - 2 = \frac{ - 16}{x + 6} [/tex]
-2(x +6)= -16
Divide both sides by -2:
x +6= -16 ÷(-2)
x +6= 8
Subtract both sides by 6:
x= 8 -6
x= 2
Alex drives at an average speed that is 1 6 of the average speed that Roy's train travels. Alex takes 20 minutes to travel 12 km in her car. Roy travels for 2 hours and 20 minutes on his train. How far does Roy travel to 2 dp?
Answers
Answer:
336.00?
not 100% sure though
Kate took out a subsidized Stafford loan worth $9,710 to pay for college. The interest rate on the loan was 5. 9%, compounded monthly. It took Kate 5 years to pay off the loan after graduation. What portion of the total amount she paid represented the interest? a. $11,236. 22 b. $9,710. 00 c. $1,526. 22 d. $2,942. 37.
Answers
Answer:
the answer is 10,0000
Step-by-step explanation:
Help again please
A stack of 400 pieces of paper is 1.800 inches tall.
A. Derion guesses that each piece of paper is 0.015 inches thick. Explain how you know that Derion’s answer is not correct.
B. Compute the thickness of each piece of paper. Show your reasoning.
Answers
Select the correct answer.
Which equation represents the line that is perpendicular to y = 1/5 and passes through (-4,-3)?
A.X=-4
B.X=-3
C. y=-5
D. y=-3
Answers
Step-by-step explanation:
The answer is b for sure.
PLEASE NO LINKS AND NO NEGATIVITY
Answers
Explanation: The order of operations is distributive property so think of it as
(1/2 • 8) - (1/2 • 4g) Also just think of dodging 8 and 4 by two since 1/2 in a number format is .5 and 8 mutuales by .5 is 4 and 4 is 2.
Hope this helps!
Can someone please take the time out of their day and help me with this question
Answers
Answer:
76, 76 104
Step-by-step explanation:
Angle 3 is vertical so it is congruent to Angle 2.
Angle 6 is corresponding, so it is congruent to Angle 2.
Angle 8 is linear to Angle 6, so they add to 180
Answer:
see explanation
Step-by-step explanation:
(a)
∠ 2 and ∠ 3 are vertically opposite angles and are congruent , then
∠ 3 = 76°
(b)
∠ 3 and ∠ 6 are corresponding angles and are congruent , then
∠ 6 = 76°
(c)
∠ 2 and ∠ 8 are same- side exterior angles and sum to 180° , that is
∠ 8 + 76° = 180° ( subtract 76° from both sides )
∠ 8 = 104°
Write an absolute value inequality to represent the situation.
What is the range of the number for calories in the chicken.
The menu at Jeanne's favorite restaurant states that the roasted chicken with vegetables entree typically contains 480 Calories. Based on the size of the chicken, the actual number of Calories in the entree can vary by as many as 40 Calories from this amount.
Answers
Answer:
|x-480|<=40
Step-by-step explanation:
The absolute distance on the number-line from x to 480 has to be 40.
|x-val| <= error-margin
|x-480| <= 40
Sam runs 6 miles in 55 minutes. At the same rate, how many miles would he run in 44 minutes?
Answers
Answer:
4.8
Step-by-step explanation:
6/55= ~0.109
0.109*44=4.8
Need help now pls on HS geometry
Answers
Answer:
b
Step-by-step explanation:
RT is a perpendicular bisector of QS , then
Δ QRS is isosceles with 2 congruent legs , that is
QR = SR
7x - 22 = 4x + 5 ( subtract 4x from both sides )
3x - 22 = 5 ( add 22 to both sides )
3x = 27 ( divide both sides by 3 )
x = 9
Then
RS = 4x + 5 = 4(9) + 5 = 36 + 5 = 41
Complete the table if x & y vary inversely
Answers
Answer:
(. ❛ ᴗ ❛.)(. ❛ ᴗ ❛.)(. ❛ ᴗ ❛.)(. ❛ ᴗ ❛.)(. ❛ ᴗ ❛.)
Adrian purchases a book for $9.86 and a poster for $3.49. If she gives the cashier
$15.00, how much change should she receive? (Don't worry about taxes!)
Answers
Daniel went to Target and bought a magazine for $5.99, a book for $15.99, and a DVD for $20.99. What was his total bill including 6% sales tax?
Answers
.06 times 42.97= 2.58
2.58+42.97= 45.55
Carson rides his bike for 30 mins each day he rides a total of 12 miles every 3 days how many days will it take to ride a total of 80 miles
Answers
Answer:
20 days
Step-by-step explanation:
If he rides 12 miles every 3 days, then he rides 4 miles in one day. Divide 80 / 4 and you get 20 days.
what is ur favorite character from boondocks mine is Riley freeman and also Huey freeman
Answers
Answer:lol
Step-by-step explanation:
What expression is equal to 4/8
Answers
Answer:
The value of 12/24 is equals to 0.5. Hence, this fraction is equivalent to 4/8.
Step-by-step explanation:
im not sure tho. hope u get it right.
46 degrees and x
X =
Answers
Answer:
136° that's 90 plus 46.........
Answer:
x = 136°
Step-by-step explanation:
The exterior angle of a triangle is equal to the sum of the 2 opposite interior angles.
x is an exterior angle of the triangle , then
x = 90° + 46° = 136°
Mateus recorded the number of miles driven and the amount
of gasoline used in the table below.
Gas Mileage
Distance Gas Usage
(in miles) (in gallons)
105
5
210
10
315
15
420
20
At this rate, what is the maximum miles that can be driven
with 12 gallons of gasoline?
A) 220 miles
B) 236 miles
C) 252 miles
D) 262.5 miles
Answers
Answer:
C. 252 miles.
Step-by-step explanation:
Since we already know how many miles is driven for 10 gallons of gas, we only need to find 2.
Since 105 miles runs on 5 gallons, divide 105 by 5 to find out how many miles runs on 1 gallon.
105/5=21
Then, multiply that by 2 to find out how many miles run on 2 gallons of gas.
21x2=42.
Finally, add 42 to 210 to get the amount of miles that runs on 12 gallons of gas.
210+42=252
Write an exponential function to model each situation. Find each amount after the
specified time.
A population of 1,236,000 grows 1.3% per year for 10 years
Answers
After 10 years, the population would grow to become 17,039,309.59 people. You can round up to 17,039,310 people if the question asks to round to the nearest person.
The property of 12x2-7=6-2x2+2
Answers
14x^2-15=0
a=14 , b =0 , c=-15
0^2-4x14x(-15) =
840
The chess clubs at school decides to give $400 to a charity at Christmas time. If the chess club raised $1,000 fund raising. What percent of the fund raiser did they donate to charity
Answers
Answer: 40%
Step-by-step explanation:
To find the percent, divide the amount donated by the full amount of money raised. 400/1000 = 0.4.
Now to make this into a percentage, multiply the answer by 100. 0.4 * 100 = 40.
Percent of the fund raiser did they donate to charity 40%
What is percentage ?In mathematics, a percentage is a number or ratio that can be expressed as a fraction of 100. If we have to calculate percent of a number, divide the number by the whole and multiply by 100. Hence, the percentage means, a part per hundred. The word per cent means per 100. It is represented by the symbol “%”.
Percentages have no dimension. Hence it is called a dimensionless number. If we say, 50% of a number, then it means 50 per cent of its whole.
To find the percent,
divide the amount donated by the full amount of money raised. 400/1000 = 0.4.
Now to make this into a percentage,
multiply the answer by 100. 0.4 * 100 = 40.
To learn more about the percentage here:
https://brainly.com/question/29224972
#SPJ7
will mark brainleist pls help
Answers
Step-by-step explanation:
Angle c + angle d = 180° ( linear pair)
given,
angle c = 5x + 9
angle d = 5x - 6
now,
5x + 9 + 5x - 6 = 180
10x + 3 = 180
10x = 180 - 3 = 177
10x = 177
x = 177/10 = 17.7
so,
angle C = 5x + 9 = 5(17.7) + 9 = 97.50°
angle D = 5x - 6 = 5(17.7) - 6 = 82.50°
Hope this answer helps you dear! take care!.
What are the real and imaginary parts of the complex number ? 16 + 3i
Answers
Answer:
Real - 16 Imaginary - 3i
Step-by-step explanation:
If the number has i with it, it's imaginary. If it doesn't have i with it, it's real
Write 2^100 as a power with the following base of 32.
Answers
Answer:
your answer is 30
Step-by-step explanation:
I have completed the test
What is the slope of the line through (2, -1) and (-2, -3)?
Answers
[tex]\text{Given that,}\\\\\\(x_1,y_1) = (2,-1)~~\text{and}~~ (x_2,y_2) = (-2,-3)\\\\\\\text{Slope,}~ m =\dfrac{y_2-y_1}{x_2 -x_1} = \dfrac{-3+1}{-2-2} = \dfrac{-2}{-4} = \dfrac 12[/tex]
Answer:
Step-by-step explanation:
Using slope formula:
(y2-y1)/(x2-x1)
(-3 + 1) / (-2-2)
-2/-4
slope: 1/2
What is the answer to X=7-3y And 2x-4y=-6
I need it
Answers
Answer:
x = − 3 y + 7
Step-by-step explanation:
Reorder 7 and − 3
Plz help. I need this by tomorrow or I’ll get detention.
Answers
[tex]\dfrac{6+ \sqrt{27}}{4-\sqrt3} \\\\\\=\dfrac{\left(6+\sqrt{27}\right)\left(4+\sqrt 3 \right)}{\left(4-\sqrt 3\right) \left(4+\sqrt 3\right)}\\\\\\=\dfrac{24+6\sqrt 3+4\sqrt{27}+\sqrt{27\cdot 3}}{4^2 - \left(\sqrt 3 \right)^2}\\\\\\=\dfrac{24+6\sqrt3+4\sqrt{9\cdot 3} +\sqrt{81}}{16-3}\\\\\\=\dfrac{24+6\sqrt 3 +12\sqrt 3 + 9 }{13}\\\\\\=\dfrac{33+18\sqrt 3}{13}\\\\\\\text{Hence, r = 33 and s = 18}[/tex]
3. Avery noticed that of the apples in a basket are red. There are 45 red apples in the basket.
(a) Represent the situation with an equation. Use a for the variable.
(b) Solve the equation in Part (a). Show your work.
(c) What does the solution of the equation represent in the situation?
Answers
Answer:
Step-by-step explanation:
Something missing in "noticed that of the apples." Perhaps "that 40% of . . .?"
But I'll try to answer, using an example:
Avery noticed that 30% of the apples in a basket are red. There are 45 red apples in the basket.
To find the total number of apples, X:
(0.30)X = 45
X = 150 apples total. 45, or 45/150, is 0.3 0r 30%.
Solve the equation. Please
Answers
Answer:
y=3
Step-by-step explanation:
1/4 = 3/12