You just multiple my guy. 2:3 is like 2/3. What is 2/3 of 39
39*2/3 = 26
Since it is a rectangular prism, the front and back are the same. the sides are the same and the top and bottom are the same. You would find the area of the front and back first. Since they both have the same measurements, you can find the area of one of the faces and multiply by 2.
A=BH
A= 3x5
A=15
15x2=30
So the front and back's area is 30. Now you find the area of both sides. They are both rectangle so the formula is A=BH.
A=BH
A=3x5
A=15
15x2=30
Now you find the area of the top and bottom. It is also a rectangle so you will use the same formula.
A=BH
A=3x3
A=9
9x2=18
Finally, you add all these measurements together adn that is the surface area.
This surface area of this rectangle prism is 78.
A). The area of the shaded triangle is 64cm. This is because the formula for the area of a triangle is (b x h) / 2, and the base of this triangle is 16, and the height is 8. So, 16 x 8 is 128, and 128 / 2 = 64. The area is 64cm.
B). The area of each white triangle is 32cm because we can see that the two white triangles is equal to half of the shaded triangle, so we can take the base of the shaded triangle and divide it in two. Then we can use the formula for the area of a triangle and solve for the area: (b x h) / 2 = (8 x 8) / 2 = 32. The area of one of the white triangles is 32cm.
C). Since we have solved for the area of each of the triangles, we can add up all of these individual areas to get the area for the rectangle: White triangle + white triangle + shaded triangle = 32 + 32 + 64, which is equal to 128cm, the area of the rectangle.
