ABCD is a rectangle.
BC = 5
Perimeter = 40
Calculate the area of the rectangle.
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ABCD is a rectangle.
BC = 5
Perimeter = 40
Calculate the area of the rectangle.
The perimeter of the rectangle equals:
Since we know that BC equals 5 and in a rectangle opposite sides are equal to each other, we get:
Since AB equals CD we can write the equation as follows:
Let's move 10 to the other side and change the sign accordingly:
Let's divide both sides by 2:
Now we know the length and width of the rectangle and can calculate its area:
75
Look at the rectangle ABCD below.
Side AB is 6 cm long and side BC is 4 cm long.
What is the area of the rectangle?
By definition, a rectangle is a quadrilateral with four right angles. This geometric property automatically makes opposite sides parallel and equal in length!
Absolutely! Both and are correct. Use whichever feels more comfortable - they give the same result.
It doesn't matter! In rectangles, you can call either pair of sides 'length' and 'width'. The area formula works regardless of which dimension you call length or width.
Look for the labeled measurement in the diagram. The side BC is marked with '5', so BC = 5. The diagram shows BC is one of the shorter sides of this rectangle.
Area measures how many unit squares fit inside the rectangle. When you have 15 units along one side and 5 units along the other, you get 15 × 5 = 75 unit squares total!
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