Question

show that (3x+7)^2 -84x =(3x-7)^2 by using alzabric identities​

Answer 1

Step-by-step explanation:

(3x+7)²-84x=(3x-7)²

9x²+49+42x-84x=9x²+49-42x

-42x+42x=9x²

0=9x²

x²=9

X=√9

X=+3(or)-3