Chapter 12.5, Problem 9WE

To determine

Find the method you would use to solve the quadratic equation.

Answer to Problem 9WE

  $x\in \{0,4\}$

Explanation of Solution

Given:

The equation is :

  $5x^2-20x=0$

Calculation:

The given equation $5x^2-20x=0$ is of the type $a{x}^2+bx=0$ , where a = 5 and b = -20 .

So, it can be solved by Factoring.

  $\begin{array}{l}5x^2-20x=0\\ \Rightarrow 5x(x-4)=0\\ \Rightarrow 5x=0\text{ and }x-4=0\\ \Rightarrow x=0\text{ and }x=4\end{array}$

So, $x\in \{0,4\}$