Area formulas

Using the formula for the area of a square, you can find the area when you know how long the sides are. The formula for the area of a square is A = s2 where A is the area and s is the length of a side. This area formula also allows you to find the question if you re given the answer. This is sort of like the game show Jeopardy , where you give the question. 

Twenty-five percent of 4,800 square feet is 1,200 square feet. To get the biggest pool possible, you want the area of the pool plus the deck to be 1,200 square feet (25 percent). Let the radius of your pool be represented by r. Add a 3-foot deck, and the total radius is r + 3. Now use the area formula to solve for r. 

A porous catalyst for chemical reactions has an internal surface area of 800 m2 per cm3 of bulk material. Fifty percent of the bulk volume consists of the pores (holes), while the other 50% of the volume is made up of the solid substance. Assume that the pores are all cylindrical tubules of uniform diameter d and length /, and that the measured internal surface area is the total area of the curved surfaces of the tubules. What is the diameter of each pore Hint Find the number of tubules per bulk cm3, n, in terms of l and d, by using the formula for the volume of a cylinder V = 0.25 ird2l. Then apply the surface-area formula, S = itdl, to the cylindrical surfaces of n tubules.)... 

When measuring lengths, you can use different units, such as feet, meters, inches, and so on. When finding the area, you use square units. The area measures the amount of square units inside of a figure. Here are the area formulas that you should know ... 

Table 8.4 Values of constant terms for various body surface area formulas.

The areas of common shapes, such as a triangle, a circle, and a rectangle, can be obtained using the area formulas shown in Table 7.4. It is a common practice to refer to these simple areas as primitive areas. Many composite siufaces with r ular boundaries can be divided into primitive areas. To determine the total area of a composite sutfoce, such as the one shown in Figure 7.10, we first divide the surfiice into the simpler primitive areas that make it up, and then we sum the values of these areas to obtain the total area of the composite surfiice. Examples of the more useful area formulas are shown in Table 7.4. 

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