Subject: height of a triangle
Name: Jeni
Who are you: Other

I need to know how to figure out the height of a triangle when all I know
are the sides and base. The sides are 5 and the base is 8 What do I do?
Please help:)


Hi Jeni,

The fact that you have an isosceles triangle (two sides have the same length) makes this question easier that it might otherwise be. I drew your triangle ABC and joined the midpoint of the base D to the opposite vertex.


Triangles ABD and ADC are congruent and hence it follows that angle ADC is a right angle. Hence triangle ADB s a right triangle and thus by Pythagoras' Theorem

52 = 42 + h2

Solve for h.