Question

Roots and zerossolve each equation and state the number of rootsx^2+4x-21=0

Answer 1

To solve this equation, the first step is to factor the term

`x^2+4x-21=(x+7)(x-3)=0`

Now, equal each factor to 0 and clear x

`\begin{gathered} x+7=0 \\ x=-7 \\ x-3=0 \\ x=3 \end{gathered}`

The equation has 2 roots, x=-7 and x=3