Answer
See answers below
Work Step by Step
$a) m^2-5m-14=0$
$(m-7)(m+2)=0$
$m-7=0$ or $m+2=0$
$m=7$ or $m=-2$
$b) p^2+p-20=0$
$(p-4)(p+5)=0$
$p-4=0$ or $p+5=0$
$p=4$ or $p=-5$
$c) 2a^2-15a+18=0$
$(a-6)(2a-3)=0$
$a-6=0$ or $2a-3=0$
$a=6$ or $a=\frac{3}{2}$