Question

What is A2 – (B + C) in simplest form?

Answer 1

A2 - (B + C) = (3x - 4)2 - ((x + 7)+ (x2 + 2))
A2 - (B + C) = 9x2 - 24x + 16 - (x2 + x + 9)
A2 - (B + C) = 9x2 - 24x + 16 - x2 - x - 9
A2 - (B + C) = 8x2 - 25x + 7

So, the answer is
A:
8x2 – 25x + 7

Answer 2

Answer: $8x^2 - 25x + 7$

Step-by-step explanation:

Here, $A = 3x - 4$, $B = x + 7$ and $C = x^2 + 2$

$A^2 - (B + C)= (3x-4)^2-(x+7+x^2+2)$     ( By putting the values)

= $(3x)^2+ (4)^2- 2\times 3x\times 4- x- 7 - x^2 -2$    ( solving the brackets)

=  $9x^2+ 16 - 24x - x- 7 - x^2 -2$

=  $8x^2- 25x + 7$        ( By operating like terms)

⇒ $A^2 - (B + C) = 8x^2- 25x + 7$

Thus, Option A is correct.