Question

if:
$2x {}^{2} - 2y {}^{2} = 125 \\ x - y = 2.5 \\ x + y =$
find value of x+y=?​

Answer 1

Step-by-step explanation:

given,

x-y=2.5

2x²-2y²=125

2(x²-y²)= 125

we know that,

a²-b²=(a+b)(a-b)

by using this identity,

2[(x+y)(x-y)]=125

2[(x+y)(2.5)]= 125

(x+y)(2.5)=125/2

(x+y) = 125/2*2.5

(x+y) = 125/5

(x+y) = 25

x + y = 25