As Evin is driving her car, she notices that after 1 hour her gas tank has 7.25 gallons left and after 4 hours of driving, it has 3.5 gallons of gas left in it. The rate at which she is LOSING gas is 1.25 gallonsSo, the slope is -1.25. How many gallons did she have to START?

8.50 gallons of gas.

Step-by-step explanation:

The slope in this scenario is -1.25 gallons per mile, this means that for every mile that Evin drives she is wasting 1.25 gallons of gasoline. Since she only drove 1 hour at the begining and after that hour her tank had 7.25 gallons, then we can simply add 1.25 gallons to her tank at this moment to make up for the 1 hour she drove and that would give us the total amount of gas she had before she started driving.

7.25 + 1.25 = 8.50 gallons of gas.

70.30

step-by-step explanation:

hello from mrbilldoesmath!

answer:

(7 x + 6 y) (49 x^2 - 42 x y + 36 y^2)

discussion:

the trick is to recognize that 343 = 7^3 and 216 = 6^3 and, in general,

a^3 + b^3 =   (a + b) (a^2 - a b + b^2).

in our case

343x^3+216y^3   =   (7x)^3 + (6y)^3

so take a = 7x and b = 6y in the above equation to get the answer.

you,

mrb