please help with area of right triangles!

Answer:
Step-by-step explanation:
Since the side length of one square in the grid is 1 unit, we know that the side lengths of the right triangle are 2 and 7 units.
The area of a triangle is A=1/2*b*h
A=1/2*2*7
A=1*7
A=7
So the area of the triangle is 7 square units