4x-7y=10 y=x-7 using the substitution method
y = x - 7...so we sub in x - 7 for y in the other equation4x - 7y = 104x - 7(x - 7) = 104x - 7x + 49 = 104x - 7x = 10 - 49-3x = - 39x = -39/-3x = 13y = x - 7y = 13 - 7y = 6solution is (13,6)