คำศัพท์คณิตศาสตร์
TOPIC Linear equations and straight line graphs
An equation can be represented by graph.
Three is a relationship between the equation and the shape of the graph.
A linear equation of the form y = mx + c can be represented by a straight line graph.
m determines the gradient of the straight line and c determines where the graph intercepts the y axis.
Investigation of graphs of linear equations
Write on the board:
The y number is the same as the jt number plus 1. Ask students to write down three pairs of co-ordinates which follow this rule. Plot the graph.
Change the rule:
The y number is the same as the x number plus 2.
Ask students to write down three pairs of co=ordinates which follow this rule. Plot the graph on the same set of axes.
Ask students what they notice about the gradients of the straight line graphs and the intercepts on the y axis.
Ask students to write the rule on the board as algebraic equations.
Students can then plot the graphs of the following rules:
The y number = twice the x number.
The y number = three times the x number
The y number = three times the x number plus 1
Ask students to write the rules as algebraic equations.
Students can work on their own to understand the relationship between straight line graphs and linear equations. The instructions below should help them.
Make you own rules for straight line graphs. Plot three co-ordinates and draw the graph of these rules.
Make rules with negative number and fractions as well as whole numbers.
Write the equations for each rule and label each straight line graph with its equation.
Describe any patterns you notice about the gradient of the graphs and their intercept on the y axis.Do the equations of the graphs tell you anything about the gradient and the intercept on the y axis?
TOPIC Area and perimeter of shapes
Area is the amount of space inside a shape.
Perimeter is the distance around the outside of shape.
Area can be found by counting squares or by calculation for regular shapes.