Hints for Finding Area (Familiar Figures)

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Consider the following hints for those more challenging problems involving area ...

Given Too Much Information
Be aware that a question may purposely give "extra" information as a distractor. In this problem, 32 and 28 are NOT needed to compute the area.

Find the area.
Area = ½ (24)(36)
= 432 sq.units

Pairing the Correct Information
In area problems involving "base" and "height", be sure to use the height and base that are perpendicular. The 18 should not be used, in this question, to compute area.
hint2 Find the area of this parallelogram
Area = (16)(24)
=384 sq. units
Looking Carefully at Diagram
When working with obtuse triangles, it may be necessary to look outside the triangle to find the height. In this problem, the height paired with 18 is 16, not 12.
hint3 Find area.
Area = ½(18)(16)
= 144 sq.units

Two-step Problems
It may be necessary in certain problems to find an additional piece of information before you can find the area. This problem needs Pythagorean Theorem to find missing height.
hint4 Find area of rectangle.
132 = h2 + 122; h = 5
A = (12)(5) = 60 sq.un.
Choose the Correct Information
When working with circles, be careful to choose correctly between radius and diameter.
When finding area, you need the radius. In this problem, use radius of 8, not the d = 16.
hint5 Find the area.
Round to nearest tenth.
Area = πr2 = π•82 = 64π
= 201.1 sq.units
Be Open to New Diagrams
When working with a trapezoid, the height may be measured anywhere between the two bases. It may not necessarily form a triangle.
Look carefully at diagrams.
hint6 Find area.
=190 sq. units


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