Why does my child mix up the opposite and adjacent sides?
Your child mixes up the opposite and adjacent sides, such as writing tan θ as adjacent ÷ opposite.
Why children do it
Both shorter sides look alike, and which is which changes with the angle being used. The opposite side is across from the angle and doesn't touch it; the adjacent side touches it, and so does the hypotenuse, opposite the right angle. Labelling all three from the angle, before anything else, settles it.
How to help at home
Ask them to label the sides from the angle before anything else: opposite, adjacent, hypotenuse.
The right way
Write tan θ as a fraction.
- 4/3Opposite is 4 and adjacent is 3: tan θ = 4 ÷ 3.
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