Answer: A = 6.5
B = 10.
Step-by-step explanation:
First, remember that when we have a triangle of height H and base B, the area of the triangle is:
Area = B*H/2.
A:
First, count the complete squares:
We have 6 complete squares.
Now the diagonal part:
The diagonal connects a section of 1 by 3 squares, and the shaded area is a right triangle
Then the shaded area will be half of 1 by 3.
this is 1.5 squares.
The total area of A is:
6 + 1.5 = 7.5 squares.
B:
This is more complicated.
At the beginning, we have 4 completed squares in the top right.
At the left, we have a 2 by 4 = 8 square region, where the shaded part is only a triangle rectangle.
Then the area of this triangle is half of 8 squares:
8/2 = 4 squares.
Last, at the bottom, we have two times a 2 by 1 = 2 square region, where the shaded part is a triangle rectangle.
Then the area of each triangle is 2/2 = 1 square.
And we have two of them, so there are 2 squares here.
Then the total area is:
A = 4 + 4 + 1 + 1 = 10 squares.