GMAT Official Guide Quantitative Review 2019_ Book

GMAT® Official Guide 20 19 Quantitative Review

7. Quadrilaterals
   A polygon with four sides is a quadrilateral A quadrilateral in which both pairs of opposite sides are
   parallel is a parallelogram. The opposite sides of a parallelogram also have equal length.

K ____ =L

J/4Zb __

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In parallelogramJKLM, JK II LM and JK = LM; KL II JM and KL= JM.

The diagonals of a parallelogram bisect each other (that is, KN== NM and]N = NL).

The area of a parallelogram is equal to

(the length of the altitude) x (the length of the base).

The area of JKLM is equal to 4 x 6 = 24.

A parallelogram with right angles is a rectangle, and a rectangle with all sides of equal length is a square.

The perimeter of WXYZ = 2(3) + 2(7) = 20 and the area of WXYZ is equal to 3 x 7 = 21. The diagonals

of a rectangle are equal; therefore WY = XZ = .J9 + 49 = Jss.

A quadrilateral with two sides that are parallel, as shown above, is a trapezoid The area of trapezoid

PQRS may be calculated as follows:

1-(the sum of the lengths of the bases)(the height)= 1-(QR + PS)(8) = 1(28 x 8) = 112.

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