← Maths with Martin

Level 6 free

Problem solver

Year 9: simultaneous equations, functions, solids and entrance tests. 30 lessons.

1. Algebraic fractions A fraction with x in the denominator. Conditions and cancelling. ⏱ 16 minutes Practice
2. Calculating with algebraic fractions Adding, multiplying and dividing algebraic fractions. ⏱ 17 minutes Practice
3. Equations with x in the denominator How you get rid of a fraction by multiplying, and why a check is required. ⏱ 17 minutes Practice
4. A pair of simultaneous equations Two equations, two unknowns, one solution. What that means. ⏱ 16 minutes Practice
5. The substitution method Make one unknown the subject and substitute it into the other equation. ⏱ 17 minutes Practice
6. The elimination method Add the equations so that one unknown disappears. ⏱ 17 minutes Practice
7. Word problems with simultaneous equations From a text, two equations: tickets, prices, counts of things. ⏱ 18 minutes Practice
8. Functions: a number machine What a function is, how you write it and how you read a table of values. ⏱ 16 minutes Practice
9. A linear function and its graph The rule y = ax + b, a straight line, slope and shift. ⏱ 17 minutes Practice
10. Reading graphs Read values, growth, falling and crossings from a graph. ⏱ 16 minutes Practice
11. A quadratic function (intro) The function y = x², a parabola and its symmetry. ⏱ 16 minutes Practice
12. Inverse proportion as a function The function y = k/x and its graph, a hyperbola. ⏱ 16 minutes Practice
13. Similarity of shapes The same shape, a different size. The similarity coefficient. ⏱ 16 minutes Practice
14. The similarity tests for triangles The tests AA, SAS and SSS. How to prove similarity fast. ⏱ 17 minutes Practice
15. Similarity in practice A shadow, a map and the height of a building. Similarity as a measuring tool. ⏱ 17 minutes Practice
16. Sine, cosine, tangent (intro) Ratios of sides in a right-angled triangle and what they are for. ⏱ 18 minutes Practice
17. A pyramid: surface area and volume Volume through a third of a prism, surface from the base and the faces. ⏱ 17 minutes Practice
18. A cone: surface area and volume Volume as a third of a cylinder, and surface from a circle and the lateral surface. ⏱ 17 minutes Practice
19. A sphere: surface area and volume The formulae for a sphere and calculating with the cube of the radius. ⏱ 16 minutes Practice
20. Composite solids Cut an unknown solid into known pieces and add them. ⏱ 17 minutes Practice
21. Money maths: interest and saving What interest is, how it is calculated and what a bank does with it. ⏱ 17 minutes Practice
22. Compound interest Interest on interest. Why saving speeds up with time. ⏱ 17 minutes Practice
23. Charts and graphs of data Bar, pie and line charts. And how graphs lie. ⏱ 16 minutes Practice
24. Probability (intro) Favourable divided by all. Dice, beads and fair games. ⏱ 16 minutes Practice
25. Entrance exams: calculating and fractions Typical questions on numbers, fractions and decimals. In peace. ⏱ 18 minutes Practice
26. Entrance exams: geometry Perimeters, areas, Pythagoras and a sketch as a rescue. ⏱ 18 minutes Practice
27. Entrance exams: word problems How to read the question, set up an equation and answer the question. ⏱ 18 minutes Practice
28. Entrance exams: strategy and time The order of questions, a time budget and calm on the day. ⏱ 17 minutes Practice
29. Project: a dream budget Plan your own event with a budget, percents and a reserve. ⏱ 18 minutes Practice
30. Problem solver finale A big recap of the whole level and a mix at the end. ⏱ 18 minutes Practice

Coding is still on the home page — this course does not replace it.