Equations and inequalities · Ages 12–13
Linear equations in one unknown worksheet
Covers: Equations and the balance, Unknowns on both sides, Equations with brackets, Fractions and decimals in equations, From words to an equation, Word problems with equations
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Linear equations in one unknown worksheet
Equations and inequalities · Ages 12–13
Numsprite
numsprite.com
Name:Date:Score:/48
Write each answer in the space. For word problems, show your working and write a sentence answer.
Part A: Working out and filling in (2 marks each)
1.8x + 21 = −19: take 21 from both sides, 8x = ; divide both by 8, x = .
Fill in each blank
Answer:
2.59 − 3x = 4x − 4, x =
Answer:
3.−5 − 6(x − 7) = 13, x =
Answer:
4.3(x − 7) = 5(x − 1), x =
Answer:
5.58 x = 11, x =
Answer in simplest form
Answer:
6.x2 + x5 = −28, x =
Answer:
7.May has 4 times as much money as Ka-lok. May spends $7 and Ka-lok is given $8, and then they have the same. With $x as Ka-lok's at first: May now has $(x − 7), Ka-lok has $(x + ), and solving gives x = .
Fill in each blank
Answer:
8.Ming buys 4 identical notebooks for $36 in all. With $x for one, the equation is 4x = 36, so x = .
Answer:
9.17 coins, $5 and $2, $73 in all. 5x + 2(17 − x) = 73, 3x + = 73, x = .
Fill in each blank
Answer:
Part B: Choose, or true or false (2 marks each)
10.🧊 is 1 g and 🍎 is x g. What is x?
- A. x = 6
- B. x = 5
- C. x = 3
- D. x = 7
Choose the right answer
Answer:
11.Moving terms in 9x + 11 = 3x + 18 gives 9x − 3x = 7.
True or false?
Answer:
12."4 less than 3 times x is 10": which equation is it?
- A. 3(x − 4) = 10
- B. 3x − 4 = 10
- C. 4 − 3x = 10
- D. 3x + 4 = 10
Choose the right answer
Answer:
Part C: Word problems (4 marks each)
13.It is 26°C on the peak and falling 5°C an hour. After how many hours will it be −9°C?
Working:
Answer:
14.A: $65 fee, $32 a book. B: $37 a book. 37x = 32x + 65, x = 65, x = .
Fill in each blank
Working:
Answer:
15.Put the steps of solving 5(x − 2) = 3(x + 4) in order.
- A. 5(x − 2) = 3(x + 4)
- B. 5x − 10 = 3x + 12
- C. x = 11
- D. 2x = 22
Write the letters in the right order
Working:
Answer:
16.Spent 17 of the money, $24 left. x − x7 = 24. Times 7: 7x − x = , x = .
Fill in each blank
Working:
Answer:
17.A rectangle's length is 9 cm more than 4 times its width, and its perimeter is 48 cm. With width x, which equation is right?
- A. 2(4x + 9) = 48
- B. 4x + 9 + x = 48
- C. 2(4x + 9 + x) = 48
- D. 2(4x + x) + 9 = 48
Choose the right answer
Working:
Answer:
18.A, B and C have 126. A has 3 times B's, and C 6 more than B. How many has C?
Working:
Answer:
Show the answers and working
Linear equations in one unknown worksheet: Answers and working
Part A: Working out and filling in
1. −40, −5
−19 − 21 = −40, −40 ÷ 8 = −5. Check with x = −5: 8x + 21 = −40 + 21 = −19.
2. 9
Move the x terms right and the numbers left: 59 + 4 = 4x + 3x, so 7x = 59 + 4, x = 9.
3. 4
A minus in front of the bracket: −5 − 6x + 42 = 13. So 6x = −5 + 42 − 13, x = 4.
4. −8
Open up: 3x − 21 = 5x − 5. Move terms: −21 + 5 = 5x − 3x, so 2x = −16, x = −8.
5. 885
Multiply both sides by the reciprocal, 85: x = 11 × 85 = 885. Or times 8 first, 5x = 88, then divide by 5.
6. −40
Times 10: 5x + 2x = −280, 7x = −280, x = −40.
7. 4, 8, 5
May had 4x, and after spending 7 has 4x − 7; Ka-lok with 8 more has x + 8. The same: 4x − 7 = x + 8, so x = 5.
8. 9
4x = 36; divide both sides by 4: x = 36 ÷ 4 = 9. Check: 4 notebooks at $9 make $36.
9. 34, 13
2 × 17 = 34; 3x = 73 − 34 = 39, x = 13. Supposing all were $2 gives the same: $39 short, $3 a swap.
Part B: Choose, or true or false
10. C. x = 3
2x + 4 = 10. Take 4 🧊 off each side: 2x = 6, so x = 3.
11. True
11 becomes −11 as it crosses, so the right side is 18 − 11.
12. B. 3x − 4 = 10
3 times x is 3x, and 4 less than that is 3x − 4.
Part C: Word problems
Marking: 2 for the working, 1 for the answer, 1 for the sentence.
13. 7 hours
26 − 5x = −9, 5x = 26 + 9 = 35, x = 7. From 26 down to −9 is 26 + 9 degrees, not a difference.
14. 5, 13
Each book saves $5, so 13 books make up the $65 membership.
15. A → B → D → C
Open the brackets, move and collect the terms, then divide by 2.
16. 168, 28
7 × 24 = 168, 6x = 168, x = 28. It isn't simply 24 × 7: what is left isn't 17.
17. C. 2(4x + 9 + x) = 48
Length = 4x + 9, width = x; perimeter = 2 × (length + width).
18. 30 sweets
Choosing B as x is easiest: 3x + x + (x + 6) = 126, 5x + 6 = 126, x = 24. C has 30.
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