Question

if x+y =8 and x-y=12 find x2+y2​

Answer 1

Step-by-step explanation:

If xy = 12 and x + y = 3, then value of x2 + y2 to find out

x + y = 3

Squaring both sides of equation

(x + y)² = (3)²

We know that in algebra (x + y)² = x² + y² + 2xy

Thus (x + y)² can be written as above

x² + y² + 2xy = 9

The value of xy = 12 is given in the statement, being substituted

x² + y² + 2 (12) = 9

x² + y² + 24 = 9

x² + y² = 9 - 24

x² + y² = - 15

The value of x² + y² is - 15

Answer 2

Answer:

x+y=8

-x-y=12

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y=-4

x=12+y

=12+-4

=8

2x+2y=16-8

=8