Question

x+2 is factor of 3x^+10x^+7x-2

Answer 1

Factor of it is 0
$x + 2 = 0 \\ x = - 2$
then put the value of x in equation
$3( - 2) {}^{3} + 10 {x}^{2} + 7x - 2 \\ - 24 + 40 - 14 - 2 \\ 0$