Lesson

Linear Equations

A linear equation has the variable to the first power. Solve it by undoing operations in reverse: clear brackets, move constants, then divide by the coefficient of $x$.

Practice

Q1

Solve for $x$: $3x + 5 = 20$

Show hint

$3x = 15$.

Q2

Solve for $x$: $2(x - 4) = 10$

Show hint

$x - 4 = 5$.

The same reversing strategy works throughout. Check a solution by substituting it back into the original equation.

Quiz

Q1

Solve for $x$: $4x - 7 = 9$

Show hint

Add 7, then divide by 4.

Q2

Which value solves $\dfrac{x}{3} = 6$?

Show hint

Multiply both sides by 3.

Q3

Solve for $x$: $5x = 0$