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Calculate the side length of a square whose area is 6400 decimeters squared.
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We’re given the area of a square.
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We know that when we’re dealing with squares, the area equals side times side.
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We usually write that as side squared.
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If area is equal to a side length squared, we can plug in 6400 for the area, which will be equal to the side length of that square squared.
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If we solve for ~~𝑥~~ [𝑠], we’ll find the side length.
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To do that, we need to get 𝑠 by itself.
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We currently have 𝑠 squared.
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If we take the square root of 𝑠 squared, we’ll be left with 𝑠.
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But if we take the square root of one side of the equation, we have to take the square root of the other side of the equation.
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We also need to take the square root of 6400.
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Of course at this point, if you were using a calculator, you would plug in the square root of 6400.
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But let’s consider the case where we don’t have a calculator.
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I notice that 6400 is made up of two square factors, 64 and 100.
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The square root of 6400 is the same as multiplying the square root of 64 times the square root of 100.
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And we know that the square root of 64 is eight.
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And the square root of 100 is 10.
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The side length is going to be equal to eight times 10.
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The side length would be 80.
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Let’s go back and take a look at the units.
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The area is given as decimeters squared.
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And that means that the side length was measured in decimeters.
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The side length of this square would be 80 decimeters.