# How do you solve b^2 + 5b - 35 = 3b by factoring?

Aug 7, 2015

Solve $y = {b}^{2} + 5 b - 35 = 3 b$

Ans: $\left(b - 5\right) \left(b + 7\right)$

#### Explanation:

$y = {b}^{2} + 2 b - 35 = 0$
Find 2 numbers p and q knowing sum (b = 2) and product (c =-35).
p and q have opposite signs (Rule of signs)
Factor pairs of (-35) -->...(-1, 35) (-5, 7). This sum is 2 = b.
Then p = -5 and q = 7.

Factored form:$y = \left(b - 5\right) \left(b + 7\right)$