Answer:
100㏑²
Step-by-step explanation;
first of all you find the base using the pythagoras theorem
that is, √13² - 12² =√25 = 5
so 5 is the base of the right angle in the big isoceles triangle
so the base of the isoceles triangle is 10 [5 + 5]
so for the first triangle the area is 60㏑²
the second triangle is 40㏑²
therefore 60 + 40 = 100㏑²
