This review covers all lessons in the Geometric Reasoning topic. Try each question before checking your answers.
Review Questions
Angle relationships fluency. Fluency
Find the complement of 34°.
Find the supplement of 97°.
Two parallel lines are cut by a transversal. A co-interior angle is 74°. Find its co-interior partner.
Two lines intersect. One angle is 48°. Find the vertically opposite angle and the two adjacent angles.
In a triangle, two angles are 55° and 78°. Find the third angle.
The exterior angle of a triangle is 142°. One non-adjacent interior angle is 89°. Find the other.
Triangle and quadrilateral angles. Fluency
An isosceles triangle has an apex angle of 28°. Find the base angles.
A parallelogram has one angle of 53°. Find the other three angles.
A rhombus has one angle of 118°. Find all four angles.
In a trapezium, one pair of co-interior angles is 91° and y°. Find y.
The four angles of a quadrilateral are 2x, 3x, 4x, and 51°. Find x and each angle.
In an equilateral triangle, one angle is expressed as (3m − 3)°. Find m.
Congruence and geometric proof. Understanding
Name the congruence test: two triangles with two equal angles and the included side equal.
ABCD is a parallelogram. Without measuring, explain why ▵ABC and ▵CDA are congruent, naming the test used.
Prove that the base angles of an isosceles triangle are equal, using a formal proof with a line of symmetry (bisect the apex angle).
In ▵XYZ, XY = XZ. M is the midpoint of YZ. Prove XM ⊥ YZ using congruent triangles.
Quadrilateral properties and reasoning. Understanding
A quadrilateral has diagonals that bisect each other. What type(s) could it be?
PQRS is a rectangle. The diagonal PR = 5k − 3 and SQ = 3k + 9. Find k and the diagonal length.
In a rhombus with side 13 cm and one diagonal of 10 cm, use Pythagoras to find the other diagonal.
Explain the difference between a rhombus and a square. What additional property must a rhombus have to also be a square?
Mixed geometric reasoning problem solving. Problem Solving
Lines AB and CD are parallel. Point P is between them. ∠PAB = 72° and ∠PCD = 38°. Find ∠APD, showing all steps with reasons. (Hint: draw a line through P parallel to AB and CD.)
In quadrilateral ABCD, AB = BC, AD = DC, and ∠B = 90°. Identify the type of quadrilateral, then find ∠A if ∠D = 130°.
A triangular plot of land has angles in the ratio 1 : 2 : 3. A surveyor extends the shortest side, creating an exterior angle. Find the exterior angle at the vertex with the largest interior angle, then verify using the exterior angle theorem.
ABCD is a square with side 8 cm. E is the midpoint of BC. Prove ▵ABE ≡ ▵DCE and find the length AE.