Exam Prep 2D Shapes

Which shape could be placed in the shaded box?

• parallelogram

• regular hexagon

• kite

• rhombus

• square

Answer explanation

A square is the only regular quadrilateral so it is the only shape that can go in the box.

Tags

CCSS.2.G.A.1

Which shape is in the wrong box?

(a)  

Answer explanation

E is an equilateral triangle so it is a regular polygon.

Tags

CCSS.2.G.A.1

• A

• B

• C

• D

• E

Answer explanation

A square, rectangle and rhombus all have two pairs of parallel sides. A kite has no parallel sides. The only shape that fits the description is the trapezium.

Tags

CCSS.3.G.A.1

(a)  

Answer explanation

The radius of a circle is half of the diameter. The radius is 60m so the diameter is 60 x 2 = 120

Tags

CCSS.7.G.B.4

Bob created this diagram using four identical equilateral triangles. What is the name of the shaded shape?

• Trapezium

• rectangle

• rhombus

• square

• kite

Answer explanation

The equilateral triangles are identical so each side must be the same length.

The angles are not all the same so the shape must be a rhombus.

Tags

CCSS.3.G.A.1

What is the size of angle q?

(a)  

Answer explanation

The sum of the angles in a triangle is 180. Angles in an equilateral triangle are the equal so each angles is 180 divided by 3 = 60 degrees.

Angles on a straight line add up to 180 so subtract to find the value of q.

180-60 = 120 degrees

Tags

CCSS.HSG.CO.C.11

(a)  

Answer explanation

The perimeter of the pentagon is 50cm so the length of each side must be 50 divided by 5 = 10cm.

This means the diameter of the circle is 10cm. The radius of a circle is half its diameter so the radius is 10 divided by 2 = 5cm

Tags

CCSS.3.MD.D.8

• A

• B

• C

• D

• E

Answer explanation

For the length of the sides to be a whole number, the number of sides must be a factor of 48. The factors of 48 are: 1, 2, 3, 4, 6, 8, 12, 16, 24 and 48.

7 is not a factor of 48 so the shape cannot be a regular heptagon.

Tags

CCSS.3.MD.D.8

(a)  

Answer explanation

The triangle is isosceles, so the other acute angle is also 35 degrees. The acute angle in the parallelogram is 90-35 = 55.

Parallelograms have two pairs of equal angles so the sum of the two obtuse angles is 360-55-55 = 250.

So j is 250 divided by 2 = 125

Tags

CCSS.HSG.CO.C.11