Question

If the value of polynomial $a{x}^2+5x$ at $x=2$ is 14 then a = ?

• A. 1
• B. 4
• C. 0.0
• D. 2

Answer 1

The correct option is A 1

Given,
$p\left(x\right)=a{x}^2+5x$
$p\left(2\right)=14$

The final value we get when we replace variable with a number is called the value of the polynomial.
Given, when $x$ = 2 , value of the polynomial will be 14.

Substituting $x$ = 2 in $p\left(x\right)$, we get
$p\left(2\right)=a\times 2^2+5\times 214=4a+104a=14-10a=\frac{4}{4}=1$
$\therefore a=1$