$$ \begin{aligned} (x-4)(2x+5x-3) &= 0&& \text{simplify left side} \\[1 em](x-4)(7x-3) &= 0&& \\[1 em]7x^2-3x-28x+12 &= 0&& \\[1 em]7x^2-31x+12 &= 0&& \\[1 em] \end{aligned} $$
$ 7x^{2}-31x+12 = 0 $ is a quadratic equation.
You can use step-by-step quadratic equation solver to see a detailed explanation on how to solve this equation.
This page was created using
Polynomial Equations Solver