Question

if (a+b)=2 and (a-b) =10,find the values of :1). (a^2 + b^2) .2)ab

Answer 1

a+b=2

a-b=10

2a=12

therefore,a=6

substitute a=6 in one of the equation

we get b=-4

1. 6×2-4×2

=4

2.6×-4

=-24

Answer 2

Answer :

Finding the values of a & b

(a+b) = 2 ........ (1)

(a-b) = 10 ........ (2)

Adding (1) and (2) :-

(a+b) + (a-b) = 10 +2

=> a+b+a-b = 12

=> 2a = 12

=> a = 6 .......... (3)

Now, substituting (3) in (1) :

=> (a+b) = 2

=> (6+b) = 2

=> b = 2 - 6 = - 4

Therefore, a = 6 & b = - 4

1. Value of ( a^2 + b^2 ) :

$=> \: {6}^{2} + ( { - 4}^{2} ) = 36 + 16$

$=> \: ( {a}^{2} + {b}^{2} ) = 52$

$2. \: a \times b \: = 6 \times - 4 = - 24$

Therefore, (a^2+b^2) = 52 and a*b= - 24

Hope this helps you ☺☺