How hard is 6th grade math?

Answer:

3.4625

Step-by-step explanation:

Given the equation:

Q(t)=0.05t^2 + 0.1t + 3.4 parts per million

Where t = time in years

By approximately how much will the carbon monoxide lvel change during the coming 6 months?

t = 6 months = 6/12 = 0.5 year

Q(0.5) = 0.05(0.5)^2 + 0.1(0.5) + 3.4 parts per million

Q(0.5) = 0.05(0.25) + 0.05 + 3.4

Q(0.5) = 0.0125 + 0.05 + 3.4

Q = 3.4625

Carbon monoxide level will change by approximately 3.4625 parts per million in 6 months

Answer:

[tex]x=-6[/tex]

Step-by-step explanation:

[tex]9\left(x+3\right)=4x-3[/tex]

Expand:

[tex]9x+9\times3=4x-3[/tex]

[tex]9x+27=4x-3[/tex]

Subtract 27 from both sides:

[tex]9x+27-27=4x-3-27[/tex]

[tex]9x=4x-30[/tex]

Subtract 4x from both sides:

[tex]9x-4x=4x-30-4x[/tex]

[tex]5x=-30[/tex]

Divide both sides by 5:

[tex]\frac{5x}{5}=\frac{-30}{5}[/tex]

[tex]x=-6[/tex]

Perpendicular lines have an opposite reciprocal slope, therefore, the slope of the perpendicular line is:

-1/7

So far, y = -1/7x + b. Now we need to plug in (7, 7) into x and y for our equation.

7 = -1/7(7) + b

Simplify the right side

7 = -1 + b

Add 1 to both sides

8 = b

The equation of the perpendicular line is:

y = -1/7x + 8

Answer:

The probability of getting a black pen from the bag is 13.5%.

Step-by-step explanation:

To determine the percentage probability that a black pen will be obtained from the bag, the following calculation must be performed:

12 + 20 + 5 = 37

37 = 100%

5 = X

(5 x 100) / 37 = X

500/37 = X

13.5 = X

Thus, it is determined that the totality of pens is 100%, and through a cross multiplication the percentage of the 5 black pens with respect to the total of pens is obtained.

Therefore, the probability of getting a black pen from the bag is 13.5%.

6/31. There are 6 black pens left and the red pen was removed, so the original sample size of 32 is reduced to 31.

Answer:

12 miles

Step-by-step explanation:

60 min in 1 hr and 10 min = 1 mile..... so 6, 10 min intervals..... and so 6 time 2 is 12

Answer:

the answer is C. $38.84

Step-by-step explanation:

Answer:

x(t) = 581.66 lb

Step-by-step explanation:

From the given information:

Consider the salt quantity in the tank at time t be x(t) lb.

∴ the rate of change of salt content in the tank is [tex]\dfrac{dx}{dt}= Rate \ of \ \ inflow - rate \ of \ \ outflow[/tex]

where:

the rate of inflow = salt conc. × flow rate = 3 lb/gallon × 7 gallons

=21 lb/s

rate of outflow = salt conc. in the tank  × flow rate

= x/250 ×  9

= 9x/250  lb/s

∴

[tex]\dfrac{dx}{dt} = 21 - \dfrac{9x}{250}[/tex]

[tex]\dfrac{dx}{dt} + \dfrac{9x}{250}= 21[/tex]

This is a 1st order linear differentiation,

The integrating factor if [tex]e^{^{ \int \dfrac{9}{250}\ dt}} = e^{^{ \dfrac{9t}{250} }}[/tex]

∴

[tex]e^{^{ \dfrac{9t }{250}}} \ \ x(t) = \int 21 e^{\dfrac{9t}{250}} \ dt + C[/tex]

[tex]e^{^{ \dfrac{9t }{250}}} \ \ x(t) = 21 \times \dfrac{250}{9}e^{\dfrac{9t}{250}} + C[/tex]

[tex]x(t) = \dfrac{1750}{3}+Ce^{^{\dfrac{-9t}{250}}}[/tex]     at  t = (0) and x(0) = 100 lb

Hence;

[tex]100 = \dfrac{1750}{3}+C[/tex]

[tex]C = \dfrac{1750}{3} -100[/tex]

[tex]C = - \dfrac{1450}{3}[/tex]

∴[tex]x(t) = \dfrac{1750}{3}-\dfrac{1450}{100}e^{^{\dfrac{-9t}{250}}}[/tex]

after time t = 1 minute i.e 60 s

[tex]x(t) = \dfrac{1750}{3}-\dfrac{1450}{100}e^{^{\dfrac{-9 \times 60}{250}}}[/tex]

[tex]x(t) = \dfrac{1750}{3}-\dfrac{1450}{100}e^{^{\dfrac{-540}{250}}}[/tex]

x(t) = 581.66 lb

Answer:

Idl but I believe its 2340

Step-by-step explanation:

but I could be wrong

Answer:

224 miles

Step-by-step explanation:

What you would do is take the 3 hours times the 46 mph to get 138 miles.

3*46=138

Next, multiply the 2 hours by the 43 mph to get 86 miles.

2*43=86

Lastly, you're going to add the two.

138+86=224 miles.

Answer:

the answer would be -1 5/8 in fraction form and -1.625 in decimal form

Answer:

-13/8

Step-by-step explanation:

2 = 16/8

3/8-16/8 = -13/8

Answer:

-17x³-10x²+x+9

Step-by-step explanation:

(5x³+4x²+6x-3)+(-2x³+3x²-7x+9)-(5x+3)(4x²+x-1)

(5x³+4x²+6x-3)+(-2x³+3x²-7x+9)-(20x³+5x²-5x+12x²+3x-3)

(3x³+7x²-x+6)-(20x³+17x²-2x-3)

-17x³-10x²+x+9

Answer:

Line segment: AD (without arrow)

Ray: BA (with one sided arrow)

Rays with common endpoint: AC and AD (with one sided arrow)

Intersection: AE (double sided arrow)

Collinear points: B, A, C

PLEASE MARK AS BRAINLIEST

Answer:

X(x+1)

Step-by-step explanation:

If it is wrong I'm sorry.

Answer:

1)[tex]h = \frac{3V}{\pi {r}^{2} }[/tex]

2)[tex]b = \frac{a}{2} + 2[/tex]

3)[tex]y = \frac{w - 3x}{7} [/tex]

Step-by-step explanation:

1)[tex]V= \frac{1}{3} \pi {r}^{2} h[/tex]

[tex] = > V = \frac{ \pi {r}^{2} h}{3} [/tex]

[tex] = > 3V = \pi {r}^{2} h[/tex]

[tex] = > h = \frac{3V}{\pi {r}^{2} } [/tex]

2)[tex]a=2(b-c)[/tex]

[tex] = > \frac{a}{2} = b - c[/tex]

[tex] = > b = \frac{a}{2} + c[/tex]

3)[tex]w=3x+7y[/tex]

[tex] = > w - 3x = 7y[/tex]

[tex] = > y = \frac{w - 3x}{7} [/tex]

Answer:

62.17

Step-by-step explanation:

you add 18.62 to 43.55 and get 62.17.

hope this helps.

Answer:

62.17 boom

Step-by-step explanation:

Answer: d s 5\ answer

Step-by-step explanation:

Answer:

4

Step-by-step explanation:

f(g(x)) = 3(x-2) + 10

f(g(0)) = 3x - 6 + 10

f(g(0)) = 3(0) - 6 + 10

f(g(0)) = 0 - 6 + 10

f(g(0)) = 4

Answer:

[tex]x^{20}[/tex]

Step-by-step explanation:

[tex](x^{2} )^{5}[/tex]·[tex](x^{5})^{2}[/tex]

[tex](x^{10} )[/tex] · [tex](x^{10})[/tex]

[tex]x^{20}[/tex]

Answer:

-6/11 =x

Step-by-step explanation:

We can use cross products to solve

(5x+2)/8=x/6

6 ( 5x+2) = 8x

Distribute

30x + 12 = 8x

Subtract 30x from each side

30x -30x +12 = 8x - 30x

12 = -22x

Divide each side by -22

12/-22 = -22x/-22

-6/11 =x

Answer:

3.3 recurring

Step-by-step explanation:

1) expand bracket

11-3a+6=27

2)rearrange equation

11+6=27+3a

11+6-27=3a

17-27=3a

-10=3a

-10/3=a

a=3.3 recurring

Answer:

a= - [tex]\frac{10}{3}[/tex] or -3.33

Step-by-step explanation:

[tex]11-3(a-2)=27[/tex]

subtract 11 on both sides; 27-11=16

[tex]-3(a-2)=16[/tex]

divide both sides by -3

[tex](a-2)=-\frac{16}{3}[/tex]

add 2 on both sides

[tex]a=-\frac{16}{3} +2[/tex]

a=[tex]-\frac{10}{3}[/tex]

Answer:

40 percent

Step-by-step explanation:

Use of proportion

50 (2) = 100%

20 (2) = 40%

      do the same thing; what you do on the bottom you do on the top too

Answer:

I believe it is 40%.

Step-by-step explanation:

Answer:

[tex]x=-\frac{9}{4} \\ or \:\\x = -2\frac{1}{4}[/tex]

Step-by-step explanation:

[tex]-2 (x + 1/4)+1=5\\\\-2\left(x+\frac{1}{4}\right)+1=5\\\\\mathrm{Subtract\:}1\mathrm{\:from\:both\:sides}\\\\-2\left(x+\frac{1}{4}\right)+1-1=5-1\\\\Simplify\\-2\left(x+\frac{1}{4}\right)=4\\\\\mathrm{Divide\:both\:sides\:by\:}-2\\\frac{-2\left(x+\frac{1}{4}\right)}{-2}=\frac{4}{-2}\\\\Simplify\\x+\frac{1}{4}=-2\\\\\mathrm{Subtract\:}\frac{1}{4}\mathrm{\:from\:both\:sides}\\\\x+\frac{1}{4}-\frac{1}{4}=-2-\frac{1}{4}\\\\Simplify\\x=-\frac{9}{4}\\\\x = -2\frac{1}{4}[/tex]

Answer:

The area of Chen's office (if that's what you're looking for) is 120.9 feet

Step-by-step explanation:

All I did was a = lw, the formula for finding the area of something using length and width

a = lw

a = 15.5 × 7.8

a = 120.9

Hope this helped.

Answer:

The correct option is;

Reflection over the y-axis

Step-by-step explanation:

An even function is a function that satisfies the following function equation;

f(x) = f(-x)

Therefore, for an even function, we have;

f(x) - f(-x) = 0

Which gives that the values of f(x) of the even function is the same upon reflection about the y-axis whereby the values of x changes from x to -x

Therefore, the symmetry of an even function is about the y-axis

However, an odd function is a function that satisfies the following function equation;

f(-x) = -f(x)

Therefore, reflection across the y-axis will result in an inversion of the odd function such that the odd function is not symmetrical about the y-axis as we have;

f(-x) = -f(x) ≠ f(x) which simplifies to f(x) ≠ f(-x).

Answer:60%

Step-by-step explanation:

3 divided by 5 ten times by 100 and you get 60%

Answer:

x > 1

Step-by-step explanation:

6x + 14 > 20

      -14    -14

6x > 6

/6    /6

x>1