Answer:
x
=
2
±
√
7
Explanation:
there are no whole numbers which multiply to - 3
and sum to - 4
we can solve using the method of
completing the square
the coefficient of the
x
2
term is 1
∙
add subtract
(
1
2
coefficient of the x-term
) 2 to x2 − 4 x ⇒ x 2 +2(− 2 ) x + 4 − 4 − 3 = 0 ⇒ ( x − 2 )2 − 7 =0 ⇒ ( x − 2 ) 2 = 7
take the square root of both sides
⇒ x − 2 = ± √ 7 ←
note plus or minus
⇒ x = 2 ± √ 7←
exact solutions