Ontario Grade 9 Math · MTH1W
Math, explained like you're five.
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37 of 37 ready- NumberB1.1
Numbers Have Stories
Every symbol in math was invented by someone with a real problem. Slide through the story.
- NumberB1.2 · B1.3
The Number Family Tree
Some numbers can hide inside a fraction. Some cannot. Meet the whole family tree.
- NumberB2.1
Multiply It Again and Again
A power is a tiny way to write a very long multiplication.
- NumberB2.1
Tiny and Huge
The Sun is far and a cell is small. One tidy pattern writes both of them.
- NumberB2.2
Exponent Shortcuts
Same base? Then the exponents have a simple rule. Watch the long version fold up.
- NumberB3.1
Up, Down, Owe, Have
Temperature, floors, and money all need numbers that point in two directions.
- NumberB3.2
One Piece of the Whole
A unit fraction is one piece. Every other fraction is a pile of those pieces.
- NumberB3.3 · B3.4
Where Does the Minus Live?
A minus in front, on top, or on the bottom can all mean the same thing. One does not.
- NumberB3.5
Percent Means Per 100
A percent is a rate out of 100. Drag the discount and watch the price move with it.
- AlgebraC1.1
Why Letters in Math?
Letters in math are a shortcut that took thousands of years to invent.
- AlgebraC1.2
Words Into Math
A pattern in words or pictures can become one short expression. Build it yourself.
- AlgebraC1.3
Same Value, Different Look
Two expressions can look different and still give the same answer every single time.
- AlgebraC1.4
Tidy It Up
Gather the same kinds of parts and a messy expression becomes one short line.
- AlgebraC1.5
Keep the Scale Balanced
Whatever you do to one side, do the same to the other.
- AlgebraC2.1 · C2.2 · C2.3
Tell the Computer What to Do
A script is algebra you can run. Read it, predict it, then change one number and watch.
- AlgebraC3.1
Straight vs Curvy Growth
One pattern adds the same amount each week. The other adds more every time. The graph shows it.
- AlgebraC3.2 · C4.1
Table, Graph, Equation
One taxi ride can be a table, a graph, and an equation. All three say the same thing.
- AlgebraC3.3
Which Plan Is Cheaper?
Two plans, two lines. The place they cross is the moment the answer flips.
- AlgebraC4.2
Draw the Rule
Some equations draw flat lines, some draw walls, and some draw slanted lines. Drag k and see.
- AlgebraC4.2
Which Side Counts?
An inequality does not draw a line of answers. It shades a whole side.
- AlgebraC4.3
Slide, Tilt, Flip
Move a line without bending it and its equation changes in a way you can predict.
- AlgebraC4.4
Steepness From Two Points
Two points are enough to find the climb, and the climb plus a start gives the equation.
- DataD1.1
What Data Says (and Doesn't)
A phone in a pocket collects a lot. Asking who benefits, and who could be hurt, comes first.
- DataD1.2
The Middle and the Spread
One giant number can trick an average. Learn what each measure is really saying.
- DataD1.3
Drawing the Best Line
Two variables can move together. A line through the points shows how closely.
- DataD2.1 · D2.2 · D2.3
The Model Loop
A model starts with a question you can answer with numbers, then a plan you can actually carry out.
- DataD2.4 · D2.5
How Good Is the Model?
A model can be useful and still be wrong outside the data you used. Know where it stops.
- Geometry & MeasurementE1.1 · E1.2
Shapes With Stories
Every measuring unit was somebody's idea, and every pattern on a wall follows an angle rule.
- Geometry & MeasurementE1.3
Same Size, New Units
A door does not change size when you measure it in centimetres. Only the number does.
- Geometry & MeasurementE1.4
Double the Length, Quadruple the Area
Stretch a shape and the numbers do not all grow at the same speed.
- Geometry & MeasurementE1.5
The Ladder and the Wall
In a right triangle the two short squares always add up to the long one.
- Geometry & MeasurementE1.5
Split It Into Pieces
An L-shaped garden looks hard until you cut it into two rectangles.
- Geometry & MeasurementE1.6
How Much Fits?
A cone fills exactly one third of the cylinder around it. Pour it and see.
- Financial LiteracyF1.1
Money Then and Now
A dollar is not the same dollar your grandparents had. Compare buying power, not face value.
- Financial LiteracyF1.2
Growing and Shrinking Money
Some things gain value every year and some lose it. Both are percentages of what is left.
- Financial LiteracyF1.3
The Price of Borrowing
The same sofa can cost very different totals. The rate, the term, and the down payment decide.
- Financial LiteracyF1.4
Make It Balance
A budget is a plan you change on purpose, not a list of what already happened.
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