9th Grade Systems of Equations Worksheet — Level 3 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 9th Grade systems of equations worksheet.
Success TutoringWorksheetsAnswer sheet9th Grade · Mathematics · Simultaneous Equations9th Grade Systems of Equations Worksheet — Level 3 — Practice Set 3 — Answers
Solve each pair of equations. Check your solution satisfies both equations.
1.Solve the system: 2x − 2y = −12 and 4x + 4y = 32
Answer: x = 1, y = 7
- Multiply equation 1 by 4 and equation 2 by 2 to match the x coefficients
- 8x − 8y = −48 and 8x + 8y = 64
- Subtract: −16y = −112, so y = 7
- Substitute back: x = 1
2.Solve the system: 4x + 3y = −3 and 3x − 5y = 34
Answer: x = 3, y = −5
- Multiply equation 1 by 3 and equation 2 by 4 to match the x coefficients
- 12x + 9y = −9 and 12x − 20y = 136
- Subtract: 29y = −145, so y = −5
- Substitute back: x = 3
3.Solve the system: 3x − 4y = 3 and 5x + 2y = 31
Answer: x = 5, y = 3
- Multiply equation 1 by 5 and equation 2 by 3 to match the x coefficients
- 15x − 20y = 15 and 15x + 6y = 93
- Subtract: −26y = −78, so y = 3
- Substitute back: x = 5
4.Solve the system: 4x + 3y = −11 and 5x − 2y = −31
Answer: x = −5, y = 3
- Multiply equation 1 by 5 and equation 2 by 4 to match the x coefficients
- 20x + 15y = −55 and 20x − 8y = −124
- Subtract: 23y = 69, so y = 3
- Substitute back: x = −5
5.Solve the system: 4x + y = 16 and 4x + 3y = 24
Answer: x = 3, y = 4
- Subtract equation 2 from equation 1: −2y = −8
- y = 4
- Substitute into equation 1: 4x + 4 = 16, so x = 3
6.Solve the system: 3x − 4y = 48 and 3x − 3y = 42
Answer: x = 8, y = −6
- Subtract equation 2 from equation 1: −y = 6
- y = −6
- Substitute into equation 1: 3x + 24 = 48, so x = 8
7.Solve the system: 3x + 2y = 27 and 2x − y = 4
Answer: x = 5, y = 6
- Multiply equation 1 by 2 and equation 2 by 3 to match the x coefficients
- 6x + 4y = 54 and 6x − 3y = 12
- Subtract: 7y = 42, so y = 6
- Substitute back: x = 5
8.Solve the system: 2x − y = 5 and 5x + 3y = 7
Answer: x = 2, y = −1
- Multiply equation 1 by 5 and equation 2 by 2 to match the x coefficients
- 10x − 5y = 25 and 10x + 6y = 14
- Subtract: −11y = 11, so y = −1
- Substitute back: x = 2
Marking tips
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