Answer: 60.84mm
Explanation:
The area of Triangle is:
A = 1/2 * base * height
7.8mm * 3mm = 23.4mm
23.4mm * 1/2
= 11.7mm
Now, find the area of the rectangle:
A = Base * Height
9.3mm * 7.8mm = 72.54mm
Now subtract the area of the triangle from the area of the rectangle
72.54mm - 11.7mm = 60.84mm