$$ \begin{aligned} 5^4+\frac{2x\cdot10^3}{400}-5^1 &= 0&& \text{multiply ALL terms by } \color{blue}{ 400 }. \\[1 em]400\cdot5^4+400 \cdot \frac{2x\cdot10^3}{400}-400\cdot5^1 &= 400\cdot0&& \text{cancel out the denominators} \\[1 em]250000+2000x-2000 &= 0&& \text{simplify left side} \\[1 em]2000x+248000 &= 0&& \text{ move the constants to the right } \\[1 em]2000x &= -248000&& \text{ divide both sides by $ 2000 $ } \\[1 em]x &= -\frac{248000}{2000}&& \\[1 em]x &= -124&& \\[1 em] \end{aligned} $$

This page was created using