. A gas station is charging $3 per gallon for gasoline. Let x represent the amount (in gallons) of gasoline purchased, and let f(x) represent the cost (in dollars) of x gallons of gasoline. A. Evaluate f(10) and f(15). B. When (i. E. For what value of x) is f(x) = 21?

(A) F(10) = 30, F(15) = 45

(B) x = 3

Step-by-step explanation:

According to the scenario, calculation of given data are as follows,

Charge for 1 gallon = $3

Amount of gasoline purchased = x

and x gallons cost = f(x)

So, cost for 1 gallon = f(x) ÷ x = 3

or f(x) = 3x

(A). So, for F(10)

Put value of F as 3, then

F(10) = 3 × 10 = 30

Similarly, for f(15) = 3 × 15 = 45

(B) f(x) = 21

we can put the value of f as 3, and then find the value of x,

3 (x) = 21

x = 21 ÷ 3

x = 7

idk

step-by-step explanation:

the multiples of 15 are 15, 30,45, 60, 75, 90, 105, 120, 135, 150, 165, 180, 195,   210, 225, 240, 255, 270, 285, 300, 315, 330, 345, 360, 375,   390, 405, 420, 435, 450, 465, 480, 495, 510, 525, 540, 555, 570, 585, 600, 615, 630, 645, 660, 675, 690, 705, 720, and 735.

the factors of 15 are 1, 3, 5, and 15.

hope that , fam!

-une, your fren : )