Question 117635
x+y=25 or x=25-y
x^2+y^2=313 substitute (25-y) for x in this equation & solve for y
(25-y)^2+y^2=313
625-50y+y^2+y^2=313
2y^2-50y+625-313=0
2y^2-50y+312=0
2(y^2-25y+156)=0
2(y-13)(y-12)=0
y-13=0
y=13 answer.
y-12=0
y=12 answer.
proof
12^2=13^2=33
144+169=313
313=313