zeriah
13

# I need help solving this Algebra question b2+8b+7

$b^2+8b+7 =0\\ \\ a=1, \ b=8, \ \ c=7 \\ \\\Delta = b^{2}-4ac = 8^{2}-4*1*7=64-28=36 \\ \\b_{1}=\frac{-b-\sqrt{\Delta }}{2a} =\frac{-8- \sqrt{36}}{2}=\frac{-8-6}{2}= \frac{-14}{2}=-7\\ \\b_{2}=\frac{-b+\sqrt{\Delta }}{2a} =\frac{-8+ \sqrt{36}}{2}=\frac{-8+6}{2}= \frac{-2}{2}=-1 \\ \\ \\b^2+8b+7 = (b+7)(b+1)$