Skip to content
Oak National Academy
Oak National Academy
Teachers
Pupils
New
New
Year 8

Checking and securing plotting a relationship

I can use a graphical representation to show all of the points (within a range) that satisfy a relationship.

Download all resources
Share activities with pupils
New
New
Year 8

Checking and securing plotting a relationship

I can use a graphical representation to show all of the points (within a range) that satisfy a relationship.

Download all resources
Share activities with pupils

Lesson details

Key learning points

  1. A relationship between two variables can be described using a rule.
  2. This relationship can be used to generate coordinate pairs.
  3. These pairs can be plotted on a graph.
  4. The shape of the curve made will give information about the relationship between the points.
  5. All the points on the curve satisfy the relationship.

Common misconception

All graphs are linear and if graphs are not linear you join points with straight line segments.

Explore $$n+2, 2n$$ and $$x^2$$. "I see $$n$$ and 2; they must be similar" pupils think. Get them to compare numerically, then graphically.

Keywords

  • Substitute - Substitute means to put in place of another. In Algebra, substitution can be used to replace variables with values.

Do a sorting activity for 'Linear' and 'Non-linear'. You could give them $$n^{th}$$ term expressions, ask them to generate the first five terms and sort. For a less confident class give the pupils the first five terms and ask them to sort.
Teacher tip

Licence

This content is © Oak National Academy Limited (2024), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).

Video

Skip video

Loading...

Starter quiz

Download starter quiz

6 Questions

Q1.
In algebra, when we replace variables with values we call this .
transforming
Correct answer: substituting
calculating
solving
Q2.
What is this coordinate?
An image in a quiz
$$(4,2)$$
Correct answer: $$(2,4)$$
$$2,4$$
$$4,2$$
Q3.
Which statements are true of this coordinate?
An image in a quiz
Correct answer: The $$y$$-coordinate is double the $$x$$-coordinate.
The $$y$$-coordinate is half the $$x$$-coordinate.
Correct answer: The $$y$$-coordinate is $$2$$ more than the $$x$$-coordinate.
The $$y$$-coordinate is $$2$$ more than the $$x$$-coordinate.
The $$x$$-coordinate and $$y$$-coordinate sum to $$4$$.
Q4.
What is the value of the expression $$5x-1$$ when $$x=3$$?
Correct Answer: 14, fourteen, Fourteen
Q5.
What is the value of the expression $$5x-1$$ when $$x=-3$$?
Correct answer: $$-16$$
$$-14$$
$$14$$
$$16$$
Q6.
Starting with the lowest, order the value of these expressions when $$x=2$$.
1 - $$4x-5$$
2 - $$10-3x$$
3 - $$7-x$$
4 - $$3x$$
5 - $$x+5$$

Exit quiz

Download exit quiz

6 Questions

Q1.
All of these coordinates fit the relationship $$x+y=5$$. This is an example of a relationship.
An image in a quiz
quadratic
Correct answer: linear
diagonal
constant
Q2.
What is the relationship between the $$x$$ and $$y$$ coordinates for the set $$(-1,-2)$$, $$(0,0)$$, and $$(1,2)$$?
$$x$$ is always $$1$$ away from $$y$$.
$$x$$ is always $$1$$ more than $$y$$.
$$x$$ is double $$y$$.
Correct answer: $$y$$ is double $$x$$.
Q3.
If we plot these coordinates will we see a linear relationship? $$(0,3)$$, $$(1,4)$$, $$(2,5)$$, $$(3,7)$$, and $$(4,7)$$.
Yes. This is an increasing linear relationship.
Correct answer: No. They do not fit the same rule.
It's impossible to know until we plot them.
Q4.
Match the coordinates to the respective rule.
Correct Answer:$$(1,5)$$,$$y=3x+2$$

$$y=3x+2$$

Correct Answer:$$(3,2)$$,$$x+y=5$$

$$x+y=5$$

Correct Answer:$$(5,2)$$,$$y=x-3$$

$$y=x-3$$

Correct Answer:$$(3,5)$$,$$y=2x-1$$

$$y=2x-1$$

Q5.
These coordinates all fit the relationship $$y=2x^2$$. Which words describe this relationship?
An image in a quiz
Linear
Correct answer: Non-linear
Straight line
Correct answer: Curve
Q6.
Some pupils are sharing $$36$$ sweets. As the number of pupils ($$p$$) varies, the numbers of sweets ($$s$$) each student gets varies. Which of the below represents this relationship?
$${p\over 36}=s$$
Correct answer: $${36\over p}=s$$
$${s\over 36}=p$$
$$p=36s$$