From story to answer
Define x, write the equation from the story, solve it, and state the result in words.
Why it works
The number is x; the story gives the equation.
Solving Equations · Apply · 6.2
Solve a word problem.
Read, define the variable, write the equation, solve, and interpret the answer in context. Always check that the answer makes sense.
See it work.
Watch the method
Solve a word problem
Set it up as ax + b = c, solve, then answer the question.
1
The equation
Solve for x — find the value that makes both sides equal.
2
Move the constant
Subtract 2 from both sides.
3
Divide by the coefficient
Divide both sides by 3 to get x by itself.
Practice until it feels automatic.
Your turn
Solve for x.
Type the value of x — a number or a fraction like 3/2.
streak 0
best 0
…x =
The idea underneath.
From easy to tricky.
A number is multiplied by 5, then 3 is subtracted; the result is -33. What is the number?
1
The equation
Solve for x — find the value that makes both sides equal. 5x - 3 = -33
2
Move the constant
Add 3 to both sides. 5x = -30
3
Divide by the coefficient
Divide both sides by 5 to get x by itself. x = -6
A number is multiplied by 3, then 7 is subtracted; the result is -25. What is the number?
1
The equation
Solve for x — find the value that makes both sides equal. 3x - 7 = -25
2
Move the constant
Add 7 to both sides. 3x = -18
3
Divide by the coefficient
Divide both sides by 3 to get x by itself. x = -6
A number is multiplied by 5, then 9 is subtracted; the result is -4. What is the number?
1
The equation
Solve for x — find the value that makes both sides equal. 5x - 9 = -4
2
Move the constant
Add 9 to both sides. 5x = 5
3
Divide by the coefficient
Divide both sides by 5 to get x by itself. x = 1
Where students slip.
Trap
Answering the equation, not the question.
Fix
Re-read what the problem asks for.
Trap
Not checking the answer fits.
Fix
Make sure the value makes sense.
Test yourself.
The Test
12 problems across three tiers. Auto-graded on submit. Hints and a full walkthrough on every question. Your work is saved on this device — sign in to keep it across devices.
0/12Answered
How to answerType just the value. Formatting won't trip you up — we ignore spaces, capital letters, commas, and subscript style, so
t₁ = 5, d = 3 and t1=5,d=3 both count. For a list of numbers, separate them with commas (e.g. 3, 10, 17).Core
Core (4)
C1
A number is multiplied by 5, then 9 is subtracted; the result is -24. What is the number?
Need a hint?
- Define x and write the equation.
- Solve, then answer in context.
C2
A number is multiplied by 6, then 8 is added; the result is 32. What is the number?
Need a hint?
- Define x and write the equation.
- Solve, then answer in context.
C3
A number is multiplied by 2, then 5 is subtracted; the result is 13. What is the number?
Need a hint?
- Define x and write the equation.
- Solve, then answer in context.
C4
A number is multiplied by 6, then 5 is subtracted; the result is -23. What is the number?
Need a hint?
- Define x and write the equation.
- Solve, then answer in context.
Apply
Apply (4)
A1
A number is multiplied by 2, then 7 is subtracted; the result is -13. What is the number?
Need a hint?
- Define x and write the equation.
- Solve, then answer in context.
A2
A number is multiplied by 6, then 1 is added; the result is 19. What is the number?
Need a hint?
- Define x and write the equation.
- Solve, then answer in context.
A3
A number is multiplied by 6, then 1 is added; the result is 37. What is the number?
Need a hint?
- Define x and write the equation.
- Solve, then answer in context.
A4
A number is multiplied by 5, then 8 is added; the result is 43. What is the number?
Need a hint?
- Define x and write the equation.
- Solve, then answer in context.
Extension
Extension (4)
E1
A number is multiplied by 4, then 3 is subtracted; the result is 5. What is the number?
Need a hint?
- Define x and write the equation.
- Solve, then answer in context.
E2
A number is multiplied by 4, then 4 is added; the result is 20. What is the number?
Need a hint?
- Define x and write the equation.
- Solve, then answer in context.
E3
A number is multiplied by 2, then 7 is added; the result is 3. What is the number?
Need a hint?
- Define x and write the equation.
- Solve, then answer in context.
E4
A number is multiplied by 4, then 9 is added; the result is 21. What is the number?
Need a hint?
- Define x and write the equation.
- Solve, then answer in context.