All GMAT Math Resources
Example Questions
Example Question #91 : Quadrilaterals
Give the area of the above parallelogram if .
Multiply height by base to get the area.
By the 30-60-90 Theorem:
.
The area is therefore
Example Question #92 : Quadrilaterals
Note: Figure NOT drawn to scale.
Refer to the above diagram. Give the area of Quadrilateral .
The correct answer is not among the other choices.
Apply the Pythagorean Theorem twice here.
The quadrilateral is a composite of two right triangles, each of whose area is half the product of its legs:
Area of :
Area of :
Add:
Example Question #11 : Calculating The Area Of A Quadrilateral
The above figure shows a rhombus . Give its area.
Construct the other diagonal of the rhombus, which, along with the first one, form a pair of mutual perpendicular bisectors.
By the Pythagorean Theorem,
The rhombus can be seen as the composite of four congruent right triangles, each with legs 10 and , so the area of the rhombus is
.
Example Question #12 : Calculating The Area Of A Quadrilateral
Rhombus has perimeter 48; . What is the area of Rhombus ?
Each side of a rhombus is congruent, so if it has perimeter 48, it has sidelength 12. Also, the diagonals of a rhombus are each other's perpendicular bisectors, so if they are both constructed, and their point of intersection is called , then . The following figure is formed by the rhombus and its diagonals.
is a right triangle with its short leg half the length of its hypotenuse, so it is a 30-60-90 triangle, and its long leg measures by the 30-60-90 Theorem. Therefore, . The area of a rhombus is half the product of the lengths of its diagonals:
Example Question #14 : Other Quadrilaterals
Note: figure NOT drawn to scale.
Give the area of the above trapezoid.
The area of a trapezoid with height and bases of length and is
.
Setting :
Example Question #15 : Other Quadrilaterals
Note: figure NOT drawn to scale.
Give the area of the above trapezoid.
The area of a trapezoid with height and bases of length and is
.
Setting :
Example Question #16 : Other Quadrilaterals
Note: figure NOT drawn to scale.
The above figure depicts a rhombus, .
Give the area of Rhombus .
The area of a rhombus is half the product of the lengths of its diagonals, so