You have enough paint to cover an area of 50 ft2.What is the side length of the largest square that you could paint? Round your answer to the nearest tenth of a

Question

You have enough paint to cover an area of 50 ft2.What is the side length of the largest square that you could paint? Round your answer to the nearest tenth of a foot.

Answer 1

Hi Jas,

 

There are a couple of ways of solving this problem.  Since it's an area question, a good place to start is the area formula.

For a square, A = s² (Area equals the length of a side squared; or Area equals side times side).

Now you can substitute the value they gave you for the area:

 

50 = s²

 

Then you take the square root of both sides of the equation to find the value of "s".  (You'll need a calculator for this.)

 

You'll get 7.071067 which rounds up to 7.1 . . . BUT if you check that side length by squaring it (7.1 x 7.1), you'll see you get an area bigger than 50, and you don't have enough paint for that.  So you'll have to round down to 7.

 

This makes logical sense too.  If you imagine a square with side length 7 ft, it would have an area of 49 ft² (7 x 7).  The next largest square would have sides of length 7.1 (because you have to round your answer to the nearest tenth), and if you check the area of that square (7.1 x 7.1) you find that it's too big.