How do you draw a triangle if the base angles and the altitude are given?

Start with the altitude (height) and draw that. Draw the actual length of the altitude on your paper, or draw it to scale. Naturally you'll draw it down the middle of your paper parallel to the sides...

David Beckham

First find 180 minus the vertex angle and divide that by 2 to get the other angles. Then solve the other sides by using sin(vertex angle)/base=sin(other angles)/other sides.

Any right triangle resting on a leg.

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