Question

Rewrite the equation by completing the square. x^2 + 4x − 21 = 0

( x + _ )^2 = _

Answer 1

`{x}^(2) + 4x + ( (4)/(2) )^(2) - 21 = 0 + ( (4)/(2) )^(2) \\ {x }^(2) + 4x + 4 = 4 + 21 \\ (x + 2)(x + 2) = 25 \\ {(x + 2)}^(2) = 25`

ATTACHED IS THE SOLUTION