Question

7x + 2y = 41 8x + 8y = 64

Answer 1

8x + 8y = 64 -- divide both sides by 8
x + y = 8 ---> x = 8 - y
now sub 8 - y in for x in the other equation
7x + 2y = 41
7(8 - y) + 2y = 41 -- distribute through the parenthesis
56 - 7y + 2y = 41 -- subtract 56 from both sides
-7y + 2y = 41 - 56 -- combine like terms
-5y = -15 -- divide both sides by -5
y = 3
now sub 3 in for y in either equation to find x
x + y = 8
x + 3 = 8
x = 8 - 3
x = 5

check..
8x + 8y = 64
8(5) + 8(3) = 64
40 + 24 = 64
64 = 64 (correct)

x = 5 and y = 3