Find a missing side using SOHCAHTOA — a real question, with a real drawn diagram, generated fresh right now exactly as it works in the app. Get one wrong and try again with a different one, for free, no signup needed.
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Work out the length of the marked side (1 dp)
Give your answer as a number (cm)
In a right-angled triangle, once you know one angle (other than the right angle) and one side, you can find any other side using the correct ratio above — whichever one connects the side you know to the side you want.
The trick is identifying which sides are "opposite," "adjacent," and "hypotenuse" relative to the angle you're given — the hypotenuse is always the longest side, opposite the right angle, and the other two swap roles depending on which angle you're looking from.
The full app also covers finding missing angles, 3D trigonometry, and the sine and cosine rules for non-right-angled triangles — part of 39 topics and 93 question types in total.
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