What is the opposite of adding 7?
Owen solved x + 7 = 12 by computing 12 + 7 = 19. He added again instead of undoing the addition.
Try this lessonFind the step that makes it click.
Pick a topic in math, science, chemistry, or writing. Try an example, get a clue, and practise at your pace.
No account or card needed. Practice answers stay on this page and aren’t saved.
3 lessons for “One-step equations”
Why multiply everything inside the brackets?
If you multiplied the x but left the other number alone, you have found a useful place to pause. The outside number counts copies of the whole group.
Try this lessonWhich way does the inequality flip?
Sofia divided -2x ≥ 10 by -2 and wrote x ≥ -5, keeping the symbol the way it was. The rule says it flips to ≤.
Try this lessonAlso close
How does subtracting the equations remove a variable?
When both equations share a term like 2y, that term becomes your exit: subtract the equations and it disappears.
Try this lessonWhich move comes first?
Isla solved 3x + 4 = 19 by writing 3x = 23, giving x = 23/3. She never removed the +4 before dividing.
Try this lessonHow does y = 2x + 1 help you solve x + y = 10?
Two equations with two unknowns feel harder than one. Substitution turns the pair into a single equation with one letter.
Try this lessonWhere did the negative sign go?
A negative sign belongs to the number next to it. Keeping that number together can prevent an almost-correct equation from turning into the wrong answer.
Try this lessonWhich reactant runs out first?
3.0 mol of O2 and 4.0 mol of H2: which runs out first? The ratio decides, not the smaller number.
Try this lessonWhy can't I add one more idea at the end?
Your conclusion is the last thing a reader sees, and adding a brand-new point there undoes the structure you built. It is a small fix with a large effect.
Try this lessonTry a step. See what clicks.
Work through an example, ask for a clue when you need one, then try a new question on your own.
Browse by subject
All of math, science, chemistry and writing lessons or search across the whole library above.
Learn by trying
Fill in one step at a time and check your answer. Need help? Tap “Give me a clue.”
Treat these examples as a starting point for a conversation, not as a replacement for your teacher’s guidance.
Need help with your own question? See how the family service works