The area of the rectangle below is equal to 55.
AC = 5.5
Calculate the length of side AB.
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The area of the rectangle below is equal to 55.
AC = 5.5
Calculate the length of side AB.
The area of a rectangle is equal to its length multiplied by its width.
Hence let's begin by inserting the known data into the formula:
Let's now divide both sides by 5.5:
10
Look at the rectangle below.
Side DC has a length of 1.5 cm and side AD has a length of 9.5 cm.
What is the perimeter of the rectangle?
Because area equals length × width. If 55 = AB × 5.5, then to find AB, we divide both sides by 5.5. Subtraction would only work if we were finding perimeter!
That's completely normal! Rectangle dimensions can be decimals. Just make sure your decimal is accurate and always check by multiplying back: your answer × 5.5 should equal 55.
It doesn't matter which you call length or width! In rectangles, you just need two perpendicular sides. AB and AC are perpendicular, so AB × AC = 55 works perfectly.
No, the area formula is essential here! We're told the area is 55 and one side is 5.5. The only way to find the unknown side is using .
You'd get 302.5, which is way too big! Remember: we need to work backwards from the area. Since Area ÷ known side = unknown side, we divide, not multiply.
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