Question

If x+y = 1 and x- y = 7 .Find the value of 5(x^2 + y ^2). ​

Answer 1

x+y = 1 and x- y = 7 .

If x+y whole square is 1 and x-y whole square is 49 so

X+y whole square + x-y whole square = 2(  x^2 + y^2).

so 49+1/2=x^2 + y^2).

25=(x^2 + y^2).

Answer 2

Answer is 125.

HOPE IT WILL HELP :-)