Algebra
43 free practice questions with explanations
PassNova has 43 free GCSE Maths Foundation practice questions on Algebra, each with a clear explanation. Practise them in the browser with instant feedback — 100% free, no sign-up, on any device. Updated for 2026.
Algebra: example questions & answers
40 worked examples with answers and explanations below. Practise all 43 Algebra questions free in the browser, with instant feedback on every answer.
Simplify 3a + 2b + a - b.
- A4a + b✓
- B4a + 3b
- C3a + 2b
- D5ab
Answer: Collect like terms: 3a + a = 4a, and 2b - b = b. So 3a + 2b + a - b = 4a + b.
Expand 3(x + 4).
- Ax + 12
- B3x + 4
- C3x + 7
- D3x + 12✓
Answer: Multiply each term inside the bracket by 3: 3 × x + 3 × 4 = 3x + 12.
Solve x + 5 = 12.
- Ax = 17
- Bx = 7✓
- Cx = -7
- Dx = 2.4
Answer: Subtract 5 from both sides: x + 5 - 5 = 12 - 5, so x = 7.
Solve 2x = 16.
- Ax = 18
- Bx = 8✓
- Cx = 32
- Dx = 14
Answer: Divide both sides by 2: 2x ÷ 2 = 16 ÷ 2, so x = 8.
If y = 3x + 2, what is y when x = 4?
- A10
- B9
- C12
- D14✓
Answer: Substitute x = 4: y = 3(4) + 2 = 12 + 2 = 14.
Simplify 5x × 2y.
- A10xy✓
- B5xy × 2
- C10x + y
- D7xy
Answer: 5x × 2y = (5 × 2) × (x × y) = 10xy.
Expand 2(3x - 5).
- A6x - 5
- B3x - 10
- C5x - 5
- D6x - 10✓
Answer: 2 × 3x = 6x, and 2 × (-5) = -10. So 2(3x - 5) = 6x - 10.
Solve 3x - 2 = 10.
- Ax = 12
- Bx = 8
- Cx = 2.67
- Dx = 4✓
Answer: Add 2 to both sides: 3x = 12. Divide by 3: x = 4.
Factorise 6a + 9.
- A6(a + 1.5)
- B3(2a + 3)✓
- C2(3a + 4.5)
- D3(a + 3)
Answer: Find the highest common factor: HCF(6, 9) = 3. So 6a + 9 = 3(2a + 3).
What is the next term in the sequence 2, 5, 8, 11, ...?
- A12
- B13
- C14✓
- D15
Answer: The sequence increases by 3 each time (2→5, 5→8, 8→11). So the next term is 11 + 3 = 14.
What is the nth term formula for the sequence 3, 6, 9, 12, ...?
- An + 2
- Bn + 3
- C3n✓
- D3n + 3
Answer: Each term is 3 times its position: 1st term = 3(1) = 3, 2nd term = 3(2) = 6, 3rd term = 3(3) = 9. The nth term is 3n.
Expand (x + 2)(x + 3).
- Ax² + 6x + 5
- B2x + 5
- Cx² + 5x + 6✓
- Dx² + 6
Answer: x(x+3) + 2(x+3) = x² + 3x + 2x + 6 = x² + 5x + 6.
Solve 4x + 3 = 2x + 11.
- Ax = 2
- Bx = 4✓
- Cx = 14
- Dx = 8
Answer: Subtract 2x from both sides: 2x + 3 = 11. Subtract 3: 2x = 8. Divide by 2: x = 4.
Simplify 12x² ÷ 3x.
- A9x
- B12x
- C4x✓
- D4x²
Answer: 12x² ÷ 3x = (12 ÷ 3) × (x² ÷ x) = 4 × x = 4x.
What is the 5th term in the sequence 1, 4, 7, 10, ...?
- A13✓
- B14
- C15
- D16
Answer: The sequence increases by 3. The terms are: 1st = 1, 2nd = 4, 3rd = 7, 4th = 10, 5th = 13.
Factorise 8a - 12.
- A4(2a - 3)✓
- B2(4a - 6)
- C8(a - 1.5)
- D4(2a - 12)
Answer: HCF(8, 12) = 4. So 8a - 12 = 4(2a - 3).
If p = 2q - 3, what is p when q = 5?
- A13
- B-1
- C7✓
- D10
Answer: Substitute q = 5: p = 2(5) - 3 = 10 - 3 = 7.
Expand 5(2x + 4) - 3x.
- A10x + 1
- B7x + 20✓
- C10x + 20
- D7x + 40
Answer: 5(2x + 4) = 10x + 20. Then 10x + 20 - 3x = 7x + 20.
Solve 2x + 5 = 3x - 1.
- Ax = -4
- Bx = 4
- Cx = 6✓
- Dx = -6
Answer: Subtract 2x: 5 = x - 1. Add 1: 6 = x, so x = 6.
What is the nth term formula for 5, 10, 15, 20, ...?
- An + 5
- B10n - 5
- C5n✓
- D5n + 5
Answer: Each term is 5 times its position. 1st = 5(1) = 5, 2nd = 5(2) = 10, etc. The nth term is 5n.
Solve 2x + 5 = 13.
- Ax = 9
- Bx = 6
- Cx = 4✓
- Dx = 2
Answer: 2x + 5 = 13. Subtract 5: 2x = 8. Divide by 2: x = 4.
Solve 3x - 7 = 11.
- Ax = 6✓
- Bx = 4
- Cx = 3
- Dx = 5
Answer: 3x - 7 = 11. Add 7: 3x = 18. Divide by 3: x = 6.
Solve x/4 + 3 = 8.
- Ax = 16
- Bx = 20✓
- Cx = 12
- Dx = 5
Answer: x/4 + 3 = 8. Subtract 3: x/4 = 5. Multiply by 4: x = 20.
Which is the solution to 2x + 3 > 11?
- Ax > 3
- Bx > 7
- Cx > 4✓
- Dx > 5
Answer: 2x + 3 > 11. Subtract 3: 2x > 8. Divide by 2: x > 4.
Make x the subject of y = 4x - 7.
- Ax = (y - 7)/4
- Bx = 4y + 7
- Cx = (y + 7)/4✓
- Dx = y/4 + 7
Answer: Add 7 to both sides: y + 7 = 4x. Then divide both sides by 4: x = (y + 7)/4.
Solve 5x - 2 ≤ 18.
- Ax ≤ 3
- Bx ≤ 5
- Cx ≤ 4✓
- Dx ≤ 6
Answer: 5x - 2 ≤ 18. Add 2: 5x ≤ 20. Divide by 5: x ≤ 4.
Solve the simultaneous equations: x + y = 7 and x - y = 3.
- Ax = 4, y = 3
- Bx = 6, y = 1
- Cx = 2, y = 5
- Dx = 5, y = 2✓
Answer: Adding the equations: (x + y) + (x - y) = 7 + 3, so 2x = 10 and x = 5. Then 5 + y = 7 gives y = 2. So x = 5, y = 2.
Factorise x² + 7x + 12.
- A(x + 2)(x + 6)
- B(x + 1)(x + 12)
- C(x - 3)(x - 4)
- D(x + 3)(x + 4)✓
Answer: Look for two numbers that multiply to give 12 and add to give 7. Those numbers are 3 and 4, so x² + 7x + 12 = (x + 3)(x + 4).
Solve 2x + y = 8 and x - y = 1.
- Ax = 2, y = 4
- Bx = 3, y = 2✓
- Cx = 5, y = -2
- Dx = 4, y = 1
Answer: Add the equations: 3x = 9, so x = 3. Substitute into x - y = 1: 3 - y = 1, so y = 2.
What is the nth term for the sequence 5, 8, 11, 14, ...?
- A3n
- B3n + 2✓
- Cn + 4
- D2n + 3
Answer: The sequence increases by 3 each time. When n = 1, the term is 5, so 3(1) + 2 = 5. When n = 2, 3(2) + 2 = 8. So the nth term is 3n + 2.
What is the nth term for the sequence 2, 5, 10, 17, ...?
- An² + 1✓
- Bn² + n
- C2n²
- D2n + 1
Answer: Differences: 3, 5, 7 (increasing by 2). These are quadratic. Testing: n² + 1: when n=1, 2; n=2, 5; n=3, 10; n=4, 17. This matches!
A function machine multiplies by 3 then adds 5. If the input is 4, what is the output?
- A12
- B17✓
- C20
- D27
Answer: Input: 4. Multiply by 3: 4 × 3 = 12. Add 5: 12 + 5 = 17.
A function machine divides by 2 then subtracts 3. If the output is 2, what was the input?
- A4
- B5
- C10✓
- D14
Answer: Work backwards from the output 2: add 3 to get 5, then multiply by 2 to get 10. The input was 10.
The nth term of a sequence is 5n + 2. What is the 10th term?
- A50
- B7
- C52✓
- D57
Answer: Substitute n = 10 into 5n + 2: 5 × 10 + 2 = 50 + 2 = 52.
Which graph represents y = 2x + 1?
- AA straight line with gradient 2 and y-intercept -1
- BA straight line with gradient 1 and y-intercept 2
- CA straight line with gradient -2 and y-intercept 1
- DA straight line with gradient 2 and y-intercept 1✓
Answer: The equation y = 2x + 1 is in the form y = mx + c, where m = 2 (gradient) and c = 1 (y-intercept).
What is the gradient of the line y = -3x + 5?
- A-5
- B3
- C5
- D-3✓
Answer: In y = mx + c, the gradient is m. Here, m = -3.
What is the y-intercept of the line y = 4x - 7?
- A7
- B-4
- C4
- D-7✓
Answer: In y = mx + c, the y-intercept is c. Here, c = -7.
A pen costs p pence. A ruler costs 30 pence more than a pen. Write an expression for the total cost, in pence, of 4 pens and 1 ruler.
- A4p + 30
- B4p + 30p
- C5p + 120
- D5p + 30✓
Answer: Four pens cost 4p and the ruler costs p + 30, so the total is 4p + p + 30 = 5p + 30 pence.
Solve 2(x + 3) = 14.
- Ax = 11
- Bx = 5.5
- Cx = 4✓
- Dx = 7
Answer: Divide both sides by 2: x + 3 = 7. Then subtract 3 from both sides: x = 4. Expanding first gives 2x + 6 = 14, which leads to the same answer.
Factorise 4x + 8.
- A4(x + 2)✓
- B2(2x + 4)
- C8(x + 1)
- D4(x + 1)
Answer: 4x + 8 = 4(x + 2). The HCF is 4.