Why does my child mix up the gradient and the y-intercept?
Your child mixes up the gradient and the y-intercept.
Why children do it
In y = 3x + 2, the two numbers look alike, and children often take whichever comes first. The gradient is the number multiplying x: how far the line rises for each step across. The y-intercept is the number on its own: where the line crosses the y-axis, when x is 0.
How to help at home
In y = mx + c, the number with x is the gradient, and the number on its own is where the line crosses the y-axis.
The right way
What is the gradient of the line y = 3x + 2?
- 3The number multiplying x is 3.
Find out where your child is
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Start the free checkRelated mistakes
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