Question

If p - q = 9 and pq = 36, evaluate
(1) p+q
(ii) p^2 - 9^2
​

Answer 1

(p-q)^2=(p+q)^2 -4pq

(9)^2= (p+q)^2 -4(36)

(p+q)^2= 225

p+q=15------1

p-q= 9--------2

adding equation 1 and 2

=> 2p= 24

=> p= 12

=> q= 15-12

= 3