Q&A for How to Find the Surface Area of a Rectangular Prism

Multiply x by the width and then by the height.

You can't find them without having additional information.

Start off with the formula for the area of a triangle: 1/2bh = a (One half of base times height equals area.) Also, you'll need to know how to find the area of a rectangle, lw = a (length times width equals area.) Make a net of the prism. If the length and width of the prism are say, l = 4 and w = 6, the bottom rectangle in the center should be 4 x 6 (area = 24 sq. units.). Next, do the other two rectangles (Cheat: They're always the same area as the base!) Now, find the area of the triangle. Say the height = 4. We know w = 6, so we multiply 4 x 6. Now we multiply that by 1/2 (divide by 2). Do the same for the other one, then add them up.

Find the surface area of each triangle (base x height), then add them together. If all the triangles are congruent, you can just find the surface area of one and multiply it by 4.

Without knowing more about the rectangular prism and the ratio of the side measurements, it would be difficult to calculate. However, if you are talking about a cube in particular, every side would measure 10 units, if the surface area is 600 units squared.

Multiply length by width, and double it. That gives you the total area of the top and bottom surfaces of the prism. Subtract that from the total surface area you were given. That leaves you with the total area of the four sides of the prism. Set that number aside for a moment. Add the length and width together and double it. That gives you the perimeter around either the top or bottom surface. Divide that perimeter into the total area of the four sides you figured out a moment ago. That gives you the height.

Multiply the width by the height. Double that number. That gives the total surface area of the two smaller ends of the prism. Subtract that figure from the total surface area of the prism. That leaves you with the total area of the other four surfaces. Let's call them the four main surfaces. Add the height to the width and double that figure. That gives you the perimeter around the four main surfaces. Divide that perimeter into the total area of the four main surfaces . That gives you the length of the prism.

Area equals length multiplied by width.

You can't without more information.

top and bottom: 16 cm^2 ea. side front and back: 16cm^2 ea. side side and side: 24cm^2 ea. side Total surface area = 112 cm^2

No. Every regular shape has its own specific formula. Irregular shapes have no formula.

Rectangular prisms do not have diameters.

Find the total surface area and subtract by the area of that particular face.

There is an infinite number of possibilities. One of them is 10" x 10" x 10".

Rectangles, squares, or prisms all have 4 angles formed by the 4 sides that connect.

To find square meters, you start by measuring the length and width of the area you're calculating using meters and centimeters and then, multiply the length and width together to get the area in square meters.

That wouldn't be possible without additional information such as length, width and height. A given surface area could contain many different volumes depending on the dimensions.

Multiply the perimeter of the base by the prism's height.

Without knowing the height of a prism, you cannot calculate its surface area (or its volume).

You come close. The volume of the sandbox is (11)(3600) = 39,600 cubic inches.

In a rectangular prism, the perimeter of the base is twice the length plus twice the width. The area of the base is the length multiplied by the width.

A rectangle measuring 8 ft by 5 ft has an area of (8)(5) = 40 square feet.

Think of this as two concentric circles, one inside the other, with respective diameters of 19 meters and 19 + 3 + 3 = 25 meters. The larger circle has an area of πr² = (π)(25/2)² = 156.25π. The smaller circle has an area of (π)(19/2)² = 90.25π. Subtract the smaller area from the larger area to find the area of the sidewalk: 156.25π - 90.25π = 66π = 207.24 square meters.

You can't do it. You have to know the length, width and height (or you have to know two of those dimensions plus the volume).

It's the same as the external surface area: 2(lw) + 2(lh) + 2(wh), where l = length, w=width and h = height.