# How do you solve -5+ 4b ^ { 2} = 31?

May 18, 2018

$b = \pm 3$

#### Explanation:

$- 5 + 4 {b}^{2} = 31$

SA: Subtract or Add by Opposite Action
$4 {b}^{2} = 31 + 5 = 36$

DM: Divide or Multiply by Opposite Action
${b}^{2} = \frac{36}{4}$
${b}^{2} = 9$

E: Exponents by Opposite Action (so Square Root)
$b = \pm \sqrt{9}$
$b = \pm 3$

P: Drop Paranthesis and start over at SA