TenMarks teaches you how to find missing measurements of figures given the area.
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Missing Measurements In this problem, we need to find the missing measure. Here, we know what area is and we need to find what the width is. Let’s quickly review area. Area is the measure of the amount of surface inside a closed boundary. Area is measured in square units. For example, square inches would be in2 or you could say square feet which would be ft2. Area is also the number of square units that cover the inside figure. Area is the measure of the amount of surface inside a closed boundary and it’s always measured in square units. Area is also the number of square units that cover the inside figure. This given figure here is a rectangle. With this rectangle, we know what the length is. We know the length is 12 centimeters. What we don’t know is the width. The width is missing. What we also know is what the area is and we know that the area is 96 cm2. We also know the formula for the area of a rectangle. The area of a rectangle is the length × width. The L is the length and W is the width. We know the formula is A=length × width. What we’re going to do is we’re just going to replace what we know. We’re going to place the A, the area with 96 and we’re going to replace our L, the length with 12 and were going to leave the W because we don’t know what this is. What were doing is solving for W. The first thing we do is we’re going to divide both sides by 12 because we want to get the W by it self. We’re going to divide it by 12. When we do that, we get W by itself and then we get 96÷12 which is 8. The width is 8, so 8=W or we can say W=8. The width of the missing measure is 8 cm. Remember that the area of a figure is the measure of the amount of surface inside a closed boundary. We use equations and substitutions of know values to calculate the missing measurements just like we did here. We used equations and substitutions of the know values to calculate the missing measure. The area of a rectangle is the length × width, were L is the length and W is the width. The area of a square is with the square with S as a side, S × S or S2. Area is measured in squared units. For example, square inches would be in2 and square feet would be ft2.