How do you solve x^2+14x + 49= 19?

1 Answer
May 22, 2018

x^2+14x+49=19 has the two solutions x=-7+-\sqrt19
(i.e. x_1=-7-\sqrt19 and x_2=-7+\sqrt19)

Explanation:

The first I notice is that 14=2*7, and 49=7^2

Please also remember that (x+a)^2=x^2+2a+a^2
Therefore x^2+14x+49=(x+7)^2=19

It follows, therefore, that
x+7=+-\sqrt19

We, therefore, have two values of x here:
x=-7+-\sqrt19