Form a rectangle, which is a parallelogram, using the triangle as shown below
Thus, the area of the rectangle is
[tex]A_{rectangle}=l*w=7*5=35[/tex]
On the other hand, the area of the triangle is half of that of the rectangle; then,
[tex]A_{triangle}=\frac{1}{2}A_{rectangle}=\frac{35}{2}=17.5[/tex]
The answer is 17.5 square units.
