Stop guessing on your math homework. Solving equations is just a game of 'undoing' what happened to $x$. If you follow the order and keep the scale balanced, you'll get the right answer every time.

To isolate the variable, you use the Order of Operations (PEMDAS) in reverse. This is often called SADMEP:

Solve for $x$:

$3x - 4 = 11$

• Step 1 (Undo Subtraction): Add $4$ to both sides. $3x = 15$
• Step 2 (Undo Multiplication): Divide both sides by $3$. $x = 5$

Test yourself on this one before you use the tool below.

Solve for $x$:

$2x + 6 = 20$

Use this tool to check your final answers for any standard equation in the format $ax + b = c$.

Note: If your equation is $4x - 5 = 15$, your "b" value is -5.