8th grade Part 1 review 3rd 9 weeks math

Triangle ABC has the following angles: Angle A is 63º. Angle B is 72º. Angle C is 45º. If triangle ABC is rotated about the origin 90º, what will the measure of Angle A' be?

• 180º

• 63º

• 90º

• 45º

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

A geometric transformation is described algebraically as shown here:

(x,y) ---> (2x, 2y)

Which best describes this transformation?

• A translation 3 units left and 3 units up

• A translation 3 units down and 3 units right

• a 180º rotation centered at the point (-2, -2)

• a dilation with a scale factor of 2.

Tags

CCSS.HSG.CO.A.2

If the point (8, -5) is reflected over the x axis of the coordinate plane, what are the corresponding coordinates of the reflected point?

• (-8, -5)

• (8,5)

• (-8, 5)

• (-5, 8)

Answer explanation

Reflecting over the x axis means that the point or shape will move UP or DOWN, which is the drection of the y axis. Therefore only the y value will change. Since a reflection means that the point(s) will be the same distance from the line of relection, te sign on the y value changes, but the number stays the same because it show that it is the same distance from the line of reflection.

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

Point Q has the coordiantes (7, -1) and is translated left 5 units. What are the new coordinates? (What are the coordinates of Q' ?)

• (12, -1)

• (7, -9)

• (2 -1)

• (1, 2)

Answer explanation

Because it is shifting left (which is the way the x axis runs - left and right), the x vslue of this point will change. The y vlue WILL NOT change, because it is not shifting up or down.

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

In the diagram, m and l are parallel and cut by a transversal. The measure of angle 8 is 135º. What argument explains why the measure of angle 6 is also 135º ?

• angle 6 and angle 8 are corresponding angles

• angle 6 and angle 8 are interior angles

• angle 6 and angle 8 are vertical angles

• angle 6 and angle 8 are alternate interior angles

Tags

CCSS.8.G.A.5

If two angles are congruent, then

• the sum of the two angles is 90º

• the sum of the two angles is 180º

• the two angles are both acute

• the two angles have equal measure

Tags

CCSS.8.G.A.2

The graph of a pair of linear equations is shown in the picture. What is the value of the x coordinate of the solution?

• -2

• -1

• 1

• 2

Tags

CCSS.8.EE.C.8B

A system of linear equations is graphed. It is shown in the picture. Which coordinate point represents the solution?

• (-3, -2)

• (-2, -3)

• (-1, -2)

• (-2, 4)

Tags

CCSS.8.EE.C.8B

Which graph shows a rectangle reflected over the x axis and then again over the y axis?

• 
• 
• 
• 

Tags

CCSS.8.G.A.3

What is the coordinate of the solution of the system of linear equations pictured?

• (3,5)

• (50, 30)

• (5,3)

• (30, 50)

Tags

CCSS.8.EE.C.8B