# How do you factor y= x^2 + 3x - 10 ?

May 13, 2016

$y = {x}^{2} + 3 x - 10 = \left(x + 5\right) \left(x - 2\right)$
Find a pair of factors of $10$ which differ by $3$.
The pair $5 , 2$ works, hence:
${x}^{2} + 3 x - 10 = \left(x + 5\right) \left(x - 2\right)$