Why does my child write y < 2x − 1 for the region above the line?
Your child writes the inequality for the other side of the line, such as y < 2x − 1 for the region above it.
Why children do it
The line is the same either way, so the inequality sign can feel like a guess. But above the line, every point's y is bigger than the line's: y > 2x − 1. Testing a point in the shaded part, in the inequality, shows whether it's the right way round.
How to help at home
Ask them to test a point in the shaded part, like (0, 5), in their inequality: is it true?
The right way
Write the inequality for the shaded region.
- y > 2x − 1The line is y = 2x - 1. Shaded above and dashed: greater, not equal.
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