Question

Solve the following quadratic by completing the square. y = x2 + 10x + 10

Answer 1

Answer:

        x = -5 - √15    or   x = -5 + √15

Step-by-step explanation:

$y = x^2+10x+10\\\\y=x^2+10x+25-25+10\\\\y=(x+5)^2-15\\\\y=0\quad\iff\quad (x+5)^2-15=0\\\\(x+5)^2=15\\\\x+5=\pm\sqrt{15}\\\\x=-5-\sqrt{15}\quad or\quad x= -5+\sqrt{15}$