Ask question

Ask question

All categories

1 year ago

7

The gas mileage for a certain vehicle can be approximated by m=−0.05x2+3.5x−49, where x is the speed of the vehicle in mph. Dete

rmine the speed(s) at which the car gets 9 mpg. Round to the nearest mph.

1 answer:

Whitepunk [10]1 year ago

4 0

Answer:

<h2>14mph</h2>

Step-by-step explanation:

Given the gas mileage for a certain vehicle modeled by the equation m=−0.05x²+3.5x−49 where x is the speed of the vehicle in mph. In order to determine the speed(s) at which the car gets 9 mpg, we will substitute the value of m = 9 into the modeled equation and calculate x as shown;

m = −0.05x²+3.5x−49

when m= 9

9 = −0.05x²+3.5x−49

−0.05x²+3.5x−49 = 9

0.05x²-3.5x+49 = -9

Multiplying through by 100

5x²+350x−4900 = 900

Dividing through by 5;

x²+70x−980 = 180

x²+70x−980 - 180 = 0

x²+70x−1160 = 0

Using the general formula to get x;

a = 1, b = 70, c = -1160

x = -70±√70²-4(1)(-1160)/2

x = -70±√4900+4640)/2

x = -70±(√4900+4640)/2

x = -70±√9540/2

x = -70±97.7/2

x = -70+97.7/2

x = 27.7/2

x = 13.85mph

x ≈ 14 mph

Hence, the speed(s) at which the car gets 9 mpg to the nearest mph is 14mph

You might be interested in

Sails come in many shapes and sizes. The sail on the right is a triangle. Is it a right triangle? Explain your reasoning.

Rudiy27

Answer:

not a right triangle

Step-by-step explanation:

you can use the pythagorean theorem to prove whether not this is a right triangle

if this triangle is a right triangle then the following equality should be true

a²+b²=c²

(9.75)²+(3.45)²=(10.24)²

(95.06)+(11.90)=(104.86)

106.96≠104.86

since the following equality is not true, this is not a right triangle.

3 0

1 year ago

Bonnie is making a dipping sauce. She mixes 150 milliliters of soy sauce with 100 milliliters of vinegar. How much soy sauce doe

Evgen [1.6K]

We have been given that Bonnie is making a dipping sauce. She mixes 150 milliliters of soy sauce with 100 milliliters of vinegar.

1. We can find amount of soy sauce Bonnie mixes with every 1 milliliter of vinegar by dividing total amount of soy sauce by total amount of vinegar.

$\text{Amount of soy sauce per ml vinegar}=\frac{150}{100}$

$\text{Amount of soy sauce per ml vinegar}=\frac{15}{10}=\frac{3}{2}$

$\text{Amount of soy sauce per ml vinegar}=1.50$

Therefore, Bonnie mixes 1.50 ml of soy sauce with every 1 ml of vinegar.

2. We can find amount of vinegar Bonnie mixes with every 1 ml of soy sauce by dividing total amount of vinegar by total amount of soy sauce.

$\text{Amount of vinegar per ml soy sauce}=\frac{100}{150}$

$\text{Amount of vinegar per ml soy sauce}=\frac{10}{15}=\frac{2}{3}$

$\text{Amount of vinegar per ml soy sauce}=0.6666666666666667\approx0.67$

Therefore, Bonnie mixes 0.67 ml of vinegar with every 1 ml of soy sauce.

7 0

2 years ago

Read 3 more answers

Complete the table of values

Agata [3.3K]

Both problems give you a function in the second column and the x-values. To find out the values of a through f, you need to plug in those x-values into the function and simplify!

You need to know three exponent rules to simplify these expressions:
1) The negative exponent rule says that when a base has a negative exponent, flip the base onto the other side of the fraction to make it into a positive exponent. For example, $3^{-2} =
\frac{1}{3^{2} }$ .
2) Raising a fraction to a power is the same as separately raising the numerator and denominator to that power. For example, $(\frac{3}{4}) ^{3} = \frac{ 3^{3} }{4^{3} }$ .
3) The zero exponent rule<span> says that any number raised to zero is 1. For example, $3^{0} = 1$ .
</span>

Back to the Problem:
Problem 1
The x-values are in the left column. The title of the right column tells you that the function is $y = 4^{-x}$ . The x-values are:
<span>1) x = 0
</span>Plug this into $y = 4^{-x}$ to find letter a:
$y = 4^{-x}\\
y = 4^{-0}\\
y = 4^{0}\\
y = 1$
<span>
2) x = 2
</span>Plug this into $y = 4^{-x}$ to find letter b:
$y = 4^{-x}\\ 
y = 4^{-2}\\ 
y = \frac{1}{4^{2}} \\ 
y= \frac{1}{16}$
<span>
3) x = 4
</span>Plug this into $y = 4^{-x}$ to find letter c:
$y = 4^{-x}\\ 
y = 4^{-4}\\ 
y = \frac{1}{4^{4}} \\ 
y= \frac{1}{256}$
<span>

Problem 2
</span>The x-values are in the left column. The title of the right column tells you that the function is $y = (\frac{2}{3})^x$ . The x-values are:
<span>1) x = 0
</span>Plug this into $y = (\frac{2}{3})^x$ to find letter d:
$y = (\frac{2}{3})^x\\
y = (\frac{2}{3})^0\\
y = 1$
<span>
2) x = 2
</span>Plug this into $y = (\frac{2}{3})^x$ to find letter e:
$y = (\frac{2}{3})^x\\ y = (\frac{2}{3})^2\\ y = \frac{2^2}{3^2}\\
y = \frac{4}{9}$
<span>
3) x = 4
</span>Plug this into $y = (\frac{2}{3})^x$ to find letter f:
$y = (\frac{2}{3})^x\\ y = (\frac{2}{3})^4\\ y = \frac{2^4}{3^4}\\ y = \frac{16}{81}$
<span>
-------

Answers:
a = 1
b = </span> $\frac{1}{16}$ <span>
c = </span> $\frac{1}{256}$
d = 1
e = $\frac{4}{9}$
f = $\frac{16}{81}$

5 0

2 years ago

PLEASE HELP ME!

dezoksy [38]

Thicknesses at different point are: <span>41, 38, 36, 29, 34, 44, 46, 43, 35, 40

In increasing order: 29, 34, 35, 36, 38, 40, 41, 43, 44, 46

Median = (38+40)/2 = 39m</span>

Median thickness is 39m

5 0

2 years ago

Read 2 more answers

Samuel was riding in the back seat of the station wagon on the way home after a long and tiring day at the

ki77a [65]

Answer: One fourth of the entire trip.

Step-by-step explanation:

The initial distance is D.

" He fell asleep halfway home."

Then he fells asleep when the distance between his actual position and his house was half of D, or:

D/2.

"He didn't wake up until he still had half as far to go as he had already

gone while asleep."

So he wakes up when his actual position is a fourth of the initial distance:

(D/2)/2 = D/4.

Then if the entire trip has a distance D, and he was sleeping between:

D/2 - D/4 = 2D/4 - D/4 = D/4.

in a trip of a distance D, he was asleep a distance of D/4.

Then, returning to the question:

How much of the entire trip home was Samuel asleep?

This is equal to the quotient between the distance that he travels asleep and the total distance:

r = (D/4)/D = 1/4.

Then he was asleep in 1/4 of the entire trip.

7 0

2 years ago