Question

If x + y = 10 & x – y = 4, find the value of x^2 – y^2.

Answer 1

x+y=10

x-y=4

Solve for x:

(x+x)+(y-y)=(10+4)

2x=14

x=7

Solve for y:

7+y=10

y=3

Prove:

7+3=10

7–3=4

Solve:

7^2-3^2=a

49-9=a

40=a

Answer:

x^2-y^2=40

hope it helps u