This study guide is designed to help you prepare for your Grade 9 Term 3 Mathematics
examination according to the CAPS curriculum. We will focus on key topics: Algebraic
Equations, Geometry of Straight Lines, and the Theorem of Pythagoras.
1. Algebraic Equations
An equation is like a balanced scale. Whatever you do to one side, you must do to the
other to keep it balanced. Our goal is to “isolate” the variable (usually 𝑥).
• Inverse Operations: To move a number, use the opposite operation.
o The inverse of addition (+) is subtraction (−).
o The inverse of multiplication (×) is division (÷).
Example Problem 1: Solve for 𝑥:
3𝑥 − 7 = 11
Solution:
• Step 1: Get rid of “−7” by adding 7 to both sides.
3𝑥 − 7 + 7 = 11 + 7
3𝑥 = 18
• Step 2: Get rid of the 3 (which is multiplying 𝑥) by dividing both sides by 3.
3𝑥 18
=
3 3
𝑥=6
Final Answer: 𝑥 = 6
2. Geometry of Straight Lines
In Grade 9, you must know the relationships between angles.
• Angles on a straight line: Sum up to 180∘.
• Vertically opposite angles: Are equal when two lines cross.
• Parallel Lines: When a line (transversal) crosses parallel lines, we look for FUN:
o F (Corresponding angles): Are equal.
o U (Co-interior angles): Sum to 180∘ .
o N (Alternate angles): Are equal.