Question

Verify whether $x=3$ is a zero of the polynomial $x^2+2x-15$.

Answer 1

Given polynomial $x^2+2x-15$

To verify: $x=3$ is a zero of the given polynomial

Solution

Consider

$x^2+2x-15$

substitute $x=3$ in the above equation

${\left(3\right)}^2+2\left(3\right)-15$

$\Rightarrow$ $9+2\left(3\right)-15$

$\Rightarrow$ $9+6-15$

$\Rightarrow$ $15-15$

$\Rightarrow$ $0$

Thus, $x=3$ is a zero of the polynomial $x^2+2x-15$