Grade 10 · Theory
Simultaneous equations
Equations and inequalities · about 3 min
Two unknowns need two equations. Solving them finds the point where both conditions are true at once.
Key points- Substitution: make one variable the subject, then substitute into the other equation.
- Elimination: add or subtract the equations to cancel one variable.
- Graphically, the solution is the point where the two lines intersect.
- Present the answer as a coordinate pair or clearly as x = …, y = ….
- Simultaneous — true at the same time.
- Intersection — the point common to both graphs.
EXAM TIP
word problems usually give you two facts — turn each into an equation before solving anything.