Find the missing side length.

To find the missing side length, we need more information. Can you provide the context of the problem or any other details that might help identify the missing side length?

on side is 21 one side is 15 one side is x

To find the missing side length x in a triangle where the other two sides are 21 and 15, we can use the Pythagorean theorem. In a right-angled triangle, the square of the length of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the other two sides.

So in this case, we have:
x^2 = 21^2 - 15^2
x^2 = 441 - 225
x^2 = 216
x = √216
x ≈ 14.7

Therefore, the missing side length is approximately 14.7.

thanks

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