Question

Verify $\frac{2}{7}$ is a zero of the polynomial $r\left(x\right)=2-7x$.

Answer 1

Zero of polynomial:

A real number $a$ is a zero (or root) of the polynomial $p\left(x\right)$ if $p\left(a\right)=0.$

Given a polynomial $r\left(x\right)=2-7x$.

We need to verify if $\frac{2}{7}$is a zero of the polynomial.

For this we need to show $r\left(\frac{2}{7}\right)=0$.

$$\begin{gathered} r\left(\frac{2}{7}\right)=2-7\left(\frac{2}{7}\right) \\ =2-2 \\ =0 \end{gathered}$$

Hence, it is verified that $\frac{2}{7}$ is a zero of the polynomial $r\left(x\right)=2-7x$.