Question

The area of a triangle with sides 10,10,12 is __ sq. units.

Answer 1

Of course I am not just going to give you the answer.

You have an isosceles triangle with a base of 12 and equal sides of 10
So sketch in the altitude, and you will have a right-angled triangle with base of 6, hypotenuse of 10 and the missing height
Use Pythagoras to find that height.
Then area of triangle = (1/2)(base)(height)