Question

what is formula of x²+y²

Answer 1

that is the formula of x2+y2= (x+y)(x+y) 

Answer 2

Given:

${x}^{2} + {y}^{2}$

To find:

the value for

${ x}^{2} + {y}^{2}$

Solution:

${x}^{2} + {y}^{2} = ( {x + y})^{2} - 2xy$

Let's consider

x = 2 and y = 3 and solve the equation.

${2}^{2} + {3}^{2} = ( {3 + 2})^{2} - 2 \times 3 \times 2$

$4 + 9 = {5}^{2} - 12$

$13 = 25 - 12$

$13 = 13$

hence proved.

The formula for

${x}^{2} + {y}^{2} = ( {x + y)}^{2} - 2xy$