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what is the length of a rectangle with a width of 5ft and an area of 30 square feet?

How would I solve this question?  Please demonstrate and so me how you got the answer. thanks

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Christina H. | Proficient in Medical, Algebra and K-12 math, BiologyProficient in Medical, Algebra and K-12 ...

Ok, well we know that the area of a rectangle or square is equal to the length multiplied by the width:
Area = Length x Width.

Out of those three things, we know that the Area is 30 square feet, and the width is 5 feet.

So we'll plug those numbers in and we get 30 ft= Length x 5 ft.

Now, let's change Length into an X since we don't know what it is yet. That gives us 30 ft2 = X times 5 ft.

To figure out X (the length) we need to get it by itself on one side of the equals sign. So to get X by itself, divide both sides by that 5 ft. When you divide the original side by the 5, it cancels itself out, and you're left with just the X.

So then that gets us something that looks like 30/5 = X.

So from here, all you need to do is simplify the left side, and that will tell us what X (the length) is!

So 30 divided by 5 = 6.

That means X (the length) is equal to 6!

I hope that helps <3


Raffi H. | Experienced and Successful Tutor and Former TeacherExperienced and Successful Tutor and For...
4.9 4.9 (695 lesson ratings) (695)

Hi Maria. I hope this helps....

Area = Length x Width

Area = 30 (given) so

30 = Length x Width

Width = 5 (given), so

30 = Length x 5

Now, divide both sides by 5, and you get

Length = 6 ft

Take good care