Solids are those annoying 3-dimensional shapes that you get on the Geometry regents and they give you a ton of formulas for but never the ones you need. So here are a few tips to help you remember the formulas for the more basic shapes.
Rectangular prism:
Now for this shape you will have to do a ton of more work. this is the shape that in 8th grade your teacher probably gave you the formula 2lw+2lh+2wh=the surface are (SA).
Well it is. The only thing is it ONLY works for RECTANGULAR prisms. This shape is pretty basic, the 'l' is the length, the 'h' is the height and the 'w' is the width.
Your next shape is a cylinder, this is one of the more easy ones, being that you already have prior knowledge of how to find the area of a circle. For this shape they give you the radius, maybe the diamater sometimes but that's okay. And the height of the radius. You multiply the radius by the height and you get your answer. Sometimes you will have to leave it in terms of Pi.
One of the more harder shapes is a pyramid. You need to know how to find the area of a regular triangle but you also need to remember that it's base is a square so it will need to be multiplied by some force (star wars re fence).
You need the are of one of the faces (the lateral area) and you will multply that by four (if it's a rectangular pyramid) So it will be 1/2*BH*4.
Rectangular prism:
Now for this shape you will have to do a ton of more work. this is the shape that in 8th grade your teacher probably gave you the formula 2lw+2lh+2wh=the surface are (SA).
Well it is. The only thing is it ONLY works for RECTANGULAR prisms. This shape is pretty basic, the 'l' is the length, the 'h' is the height and the 'w' is the width.
Your next shape is a cylinder, this is one of the more easy ones, being that you already have prior knowledge of how to find the area of a circle. For this shape they give you the radius, maybe the diamater sometimes but that's okay. And the height of the radius. You multiply the radius by the height and you get your answer. Sometimes you will have to leave it in terms of Pi.
One of the more harder shapes is a pyramid. You need to know how to find the area of a regular triangle but you also need to remember that it's base is a square so it will need to be multiplied by some force (star wars re fence).
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