Question
Find roots of polynomial $$ p(x) = x^2+2x-7x $$
Answer
The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0\\[1 em]x_2 &= 5 \end{aligned} $$Explanation
Step 1:
Combine like terms:
$$ x^2+ \color{blue}{2x} \color{blue}{-7x} = x^2 \color{blue}{-5x} $$Step 2:
Factor out $ \color{blue}{ x }$ from $ x^2-5x $ and solve two separate equations:
$$ \begin{aligned} x^2-5x & = 0\\[1 em] \color{blue}{ x }\cdot ( x-5 ) & = 0 \\[1 em] \color{blue}{ x = 0} ~~ \text{or} ~~ x-5 & = 0 \end{aligned} $$One solution is $ \color{blue}{ x = 0 } $. Use second equation to find the remaining roots.
Step 3:
To find the second zero, solve equation $ x-5 = 0 $
$$ \begin{aligned} x-5 & = 0 \\[1 em] x & = 5 \end{aligned} $$This page was created using
Polynomial Roots Calculator