Find the magnitude of side R. Show work please!

21.7 metres (assuming the triangle is a right triangle)

Step-by-step explanation:

Assuming this is a right triangle, we can simply use the Pythagorean Theorem, which states that in a right triangle with legs a and b and hypotenuse c:

a² + b² = c²

Here, a = 20, b = 8.5, and R = c. Plug these in:

a² + b² = c²

20² + 8.5² = R²

400 + 72.25 = R²

472.25 = R²

R = √472.25 ≈ 21.7 m

Thus, R is about 21.7 metres.

~ an aesthetics lover

4th option is correct xy=-10

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