Answer:
11) 5.6 cm^2 c) 12) 32.4 inches^2 a)
Step-by-step explanation:
11) The formula to find the area of a triangle is bh/2, so now we need to find the lengths of the base and height to apply the formula.
We can see that the height is 2.8 cm and the base is 4 cm. Applying the formula for the area of a triangle we have:
bh/2 plugging 2.8 and 4 in
= 4*2.8/2 simplifying
= 11.2/2 dividing
= 5.6 cm^2
Therefore the area of the triangle is 5.6 cm^2.
12) We can see that this figure is a 4 sided shape but we can also see that we can separate this shape into two shapes and calculate the area. See image.
We can cut this shape with a line to give us a triangle and a rectangle, which will enable us to solve for the area of the triangle and rectangle then we can add the areas up giving us the total area of the shape.
The triangle first we know that the base of the triangle is 4 inches because the the width of the rectangle is 4 inches too. But now we need to find the height of the triangle we can do this by subtracting 5.2 inches from 11 inches because the height of the triangle is the length of the shape itself subtracted by the length of the new rectangle that we made.
11 - 5.2 = 5.8 inches.
This gives us the height of the triangle, now we can calculate for the area using the formula bh/2. Plugging the base and height in we have:
bh/2
= 4*5.8/2 simplifying
= 23.2/2 dividing
= 11.6 inches^2..
Now we can calculate for the area of the rectangle using the measurements we already know which is the length and width of the rectangle. We know that the length is 5.2 inches and the width is 4 inches. So, we can not calculate for the area using the formula lw. Substituting 5.2 inches for the length and 4 inches for the width.\
lw
= 5.2*4 simplifying
= 20.8 inches^2.
Now we can add the area of the triangle and the rectangle together which will give us the total area of the shape.
20.8 + 11.6
= 32.4 + inches^2.
Therefore the area of the figure is 32.4 + inches^2.
