Question

How to find the missing side of this triangle

Answer 1

37 mm.

Explanation:

Use Pythagoras theorem

Missing side in small triangle = sqrt (13^2 - 5^2)

= sqrt144

= 12.

So applying the same theorem to the large triangle

x^2 = 12^2 + 35^2

x^2 = 1369

x = 37 mm.