Question

12x+3=15x solve for x

Answer 1

Have a good lessons ;)

Answer 2

$12x+3=15x\ \ \ \ |subtract\ 3\ from\ both\ sides\\\\12x=15x-3\ \ \ \ \ |subtract\ 15x\ from\ both\ sides\\\\-3x=-3\ \ \ \ \ |divide\ both\ sides\ by\ (-3)\\\\\boxed{x=1}\\\\check:\\\\L=12\cdot1+3=12+3=15\\R=15\cdot1=15\\\\L=R\ :)$