$$ \begin{aligned} \frac{1+x}{2}+\frac{3-x}{4} &= 3x^2&& \text{multiply ALL terms by } \color{blue}{ 4 }. \\[1 em]4 \cdot \frac{1+x}{2}+4\frac{3-x}{4} &= 4\cdot3x^2&& \text{cancel out the denominators} \\[1 em]2x+2+3-x &= 12x^2&& \text{simplify left side} \\[1 em]x+5 &= 12x^2&& \text{move all terms to the left hand side } \\[1 em]x+5-12x^2 &= 0&& \text{simplify left side} \\[1 em]-12x^2+x+5 &= 0&& \\[1 em] \end{aligned} $$
$ -12x^{2}+x+5 = 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
Equations Solver