Paper 1 · Algebra
⏱ Tested in 4 exam questions since 2018
Lesson 18 of 23
Algebra 18 – Simultaneous equations in three variables
You’ll learn
- Choose elimination (all linear) vs substitution (one non-linear) for a system
- Solve three equations in x, y, z by eliminating one variable from two pairs
- Label equations A–E and back-substitute to find the third unknown
- Clear fractions first and cross-multiply awkward coefficients when eliminating
Most recent exam questions
- 2024 P1 Q1(c)
- 2023 P1 Q1(a) — deferred
- 2022 P1 Q2(b)(ii)
- 2018 P1 Q1(a)
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