The equation for the area of a triangle is A = 1/2 (b)(h).
We have the base length in this triangle here, however we are missing the height. To find the height, we will need to use the Pythagorean Theorem (a^2 + b^2 = c^2). As you've sort of already done with your ruler on the triangle image, we need to separate the triangle into two right triangles. In each right triangle, we know what a and c equal (5 and 13, respectively). So, we need to plug those values into the Pythagorean Theorem in order to find the height of the triangle, which we will then use to find the area.
Pythagorean theorem:
(5^2) + (b^2) = (13^2)
25 + b^2 = 169
b^2 = 144
b = 12 cm
Area:
A = 1/2 (10)(12)
A = 1/2 (120)
A = 60 cm^2
Hope this helps!! :)
