CPM Homework Help : CCA Problem 10-38

Solve the equations below by first changing each equation to a simpler, equivalent equation. Check your solution(s). Are any values of the variable not allowed?

$50x^2+200x=-150$

$\frac{a}{9}+\frac{1}{a}=\frac{2}{3}$

$1.2m-0.2=3.8+m$

$\frac{3x}{4}+\frac{x}{3}-\frac{1}{2}=0$