# Given the coordinates for the function below, which of the following arecoordinates for its inverse?Gallons

Given the coordinates for the function below, which of the following are coordinates for its inverse?
Gallons Cost, in
of Gas Dollars
1
2
5
15
20
1.25
2.50
6.25
18.75
25.00

## This Post Has 5 Comments

1. Sawas says:

Not sure but I believe it is A

Step-by-step explanation:

2. moisescab662 says:

The equation of the function is assumed to be a straight line is of the form,

$y= mx+c$,  where  $m,c$

are the gradient and the y intercept respectively.

$m=\frac{y_2-y_1}{x_2-x_1} = \frac{-5-5}{2-0} = -5$.

The equation of the line is,

$y= -5x+c\\=5=-5(0)+c\\= c= 5$

The equation of the function is ,

$y = -5x+5.$.

The value of the x-coordinate when the y coordinate is 0 is found as shown below.

$0=-5x+5\\=x=1\\$.

so the x-coordinate is 1.

3. aaliyahthomas37 says:

g(x) = 0.8x  gal/dollar

Step-by-step explanation:

This is a direct relation, each gallon costs 1.25, 20 gal. costs 25.00, etc.

so

f(x) = 1.25x  where x = number of gal.  f(x) is the cost

The inverse relation is the reciprocal,

for each \$1.00, we can buy 1/1.25 = 0.8 gal.

or

g(x) = 0.8x  where x = amount, g(x) is number of gallons

4. imbadatmath56 says:

gimme the rest of the question then i can properly answer this question

Step-by-step explanation:

5. alyssa0888 says:

2-3+23=-34 so that is the right one