Use the image to answer the question.
An illustration shows a two-dimensional net of a triangular prism with all of its sides open and visible. The net appears as three horizontal rectangles joined next to each other. All 4 sides of the middle rectangle are drawn with dashed lines. The width of the 3 rectangles is 1 centimeter. The length of the outer rectangles is 2.5 centimeters. The length of the middle rectangle is 3 centimeters. Two right triangles adjoin the middle rectangle on the top and bottom along the 3 centimeter side, with their perpendicular height measuring 2 centimeters. A right angle is shown where the perpendicular height intersects with the triangle base.
What is the surface area of the triangular prism whose net is shown?
A:6 cm2
B:2.48 cm2
C:8 cm2
D:14 cm2
3 answers
- Area of outer rectangles = 2.5 cm x 1 cm x 2 = 5 cm2 (since there are two identical rectangles)
- Area of middle rectangle = 3 cm x 1 cm = 3 cm2
Next, we need to find the area of the two triangles. The area of a triangle is 1/2 times base times height:
- Area of top triangle = 1/2 x 3 cm x 2 cm = 3 cm2
- Area of bottom triangle = 1/2 x 3 cm x 2 cm = 3 cm2
Finally, we can add up the areas of all the faces to get the surface area of the prism:
5 cm2 + 5 cm2 + 3 cm2 + 3 cm2 + 3 cm2 = 19 cm2
However, we need to remember that the net shows all the faces of the prism, including the inside faces that we can't see. So we need to subtract the areas of the rectangles that form the inside faces. Since the inside faces are identical to the outer faces, each inside rectangle has an area of 5 cm2. There are two inside rectangles, so their combined area is 10 cm2. Subtracting this from the total surface area gives:
19 cm2 - 10 cm2 = 9 cm2
Therefore, the answer is not one of the options given.
An illustration shows a two-dimensional net of a triangular prism with all of its sides open and visible. The net appears as three horizontal rectangles joined next to each other. All 4 sides of the middle rectangle are drawn with dashed lines. The width of the 3 rectangles is 1 centimeter. The length of the outer rectangles is 2.5 centimeters. The length of the middle rectangle is 3 centimeters. Two right triangles adjoin the middle rectangle on the top and bottom along the 3 centimeter side, with their perpendicular height measuring 2 centimeters. A right angle is shown where the perpendicular height intersects with the triangle base.
What is the surface area of the triangular prism whose net is shown?
A:6 cm2
B:2.48 cm2
C:8 cm2
D:14 cm2
- Area of outer rectangles = 2.5 cm x 1 cm x 2 = 5 cm2 (since there are two identical rectangles)
- Area of middle rectangle = 3 cm x 1 cm = 3 cm2
Next, we need to find the area of the two triangles. The area of a triangle is 1/2 times base times height:
- Area of top triangle = 1/2 x 3 cm x 2 cm = 3 cm2
- Area of bottom triangle = 1/2 x 3 cm x 2 cm = 3 cm2
Finally, we can add up the areas of all the faces to get the surface area of the prism:
5 cm2 + 5 cm2 + 3 cm2 + 3 cm2 + 3 cm2 = 19 cm2
However, we need to remember that the net shows all the faces of the prism, including the inside faces that we can't see. So we need to subtract the areas of the rectangles that form the inside faces. Since the inside faces are identical to the outer faces, each inside rectangle has an area of 5 cm2. There are two inside rectangles, so their combined area is 10 cm2. Subtracting this from the total surface area gives:
19 cm2 - 10 cm2 = 9 cm2
Therefore, the answer is not one of the options given.