Homeschool → Australia → Year 9 → Mathematics
Year 9 mathematics
In Year 9, learners use Pythagoras' theorem to find unknown lengths in right-angled triangles and connect algebra with graphs by working with gradient and the equation of a straight line. They expand binomial products, work with very large and very small numbers in scientific notation, and apply similarity and scale. Statistics and probability extend to comparing distributions and two-step chance experiments.
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Number
Algebra
- Expanding binomial productsFull lesson · 50 minExpand products of two binomials such as (x + 3)(x + 5), and recognise the special patterns for perfect squares and the difference of two squares.
- Gradient and linear graphsFull lesson · 50 minCalculate the gradient of a line from two points, interpret y = mx + c, and sketch straight-line graphs from their equations.
Measurement
- Pythagoras' theoremFull lesson · 50 minUse Pythagoras' theorem to find unknown side lengths in right-angled triangles and to decide whether a triangle is right-angled.
- Surface area and volume of prisms and cylindersTopic outlineCalculate the surface area and volume of right prisms and cylinders, and solve practical problems such as painting or filling containers.