Taking an answer and finding the question

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. 

The Problem If the area of a square is 144 square inches, then what is the length of the sides of that square  

Replace the A in the formula with 144 and solve for the value of s. You get that 144 = s2. Two numbers have squares that are 144,12 and -12. Because it doesn t make any sense to have a side of a square be a negative number, then the answer must be s = 12. 

The Problem The area of a rectangle is found with the formula A = Iw, where l is the length and w is the width. If the area of a rectangle is 70 square feet, and the length of the rectangle is 10 feet, then what is the perimeter of that rectangle  

This problem has two parts. First, you solve for the width of the rectangle. Then you use the length and width in the perimeter formula P =2(1+ w) to find the perimeter of that rectangle. 

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