Answer:
c) 21 square units
Explanation:
The base of the triangle is 6 units. You can just count that along the bottom of the triangle.
Now draw a line from that top dot to the middle of the bottom line to show the height of the triangle. It's 7 units.
Area of a triangle = (1/2) * base * height
= (1/2)* 6 * 7
= (1/2) * 42
= 21 square units