Similar Triangles Calculator: Solve for Missing Sides

Calculate Missing Side in Similar Triangles

A known side length from the first triangle (e.g., base).
Another known side length from the first triangle (e.g., height).
The side in the second triangle that corresponds to Side A of Triangle 1.
The unknown side length in Triangle 2 that corresponds to Side B of Triangle 1.

Unlock the power of geometry with our Similar Triangles Calculator! Easily find unknown side lengths in similar triangles by inputting known values. Perfect for students and professionals needing quick, accurate solutions for proportional reasoning problems.

Formula:

When two triangles are similar, their corresponding sides are proportional. If we have Triangle 1 with sides S1A and S1B, and a similar Triangle 2 with corresponding side S2A, we can find its corresponding side S2B using the proportion:

S1A / S2A = S1B / S2B

Rearranging to solve for S2B:

S2B = (S2A × S1B) / S1A

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