Jefferson high school is looking to expand its student parking lot by expanding the existing lot as shown below. The size of the new parking low will be twice the size of the old parking lot. How many feet, x was the old parking lot expanded by?

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

look at the picture i have filled out a table for it. hope this .

the solution, from the graphing of the two lines, is (3,2), i.e., x = 3, y = 2.