SOLUTION: Solve the following system. Find the sum of the x and y solutions. x - y = 7 4x - 5y = 25 a) 15 b) 13 c) 11 d) 9 e) none of the above

Algebra ->  Rational-functions -> SOLUTION: Solve the following system. Find the sum of the x and y solutions. x - y = 7 4x - 5y = 25 a) 15 b) 13 c) 11 d) 9 e) none of the above      Log On


   



Question 59848: Solve the following system. Find the sum of the x and y solutions.
x - y = 7
4x - 5y = 25
a) 15
b) 13
c) 11
d) 9
e) none of the above

Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
X-Y=7 OR X=7+Y
4X-5Y=25 SO
4(7+Y)-5Y=25
28+4Y-5Y=25
-Y=-3
Y=3 THEN
X-3=7
X=7+3
X=10
PROOF
4*10-5*-3=25
40-15=25
25=25