Are the triangles congruent?
Classifying triangles and congruency statements
Review
100

Are the triangles congruent? Explain

No. SSA can form two triangles, so not guaranteed congruent.

100

Classify the triangles by sides and angles, explain: 

Since no sides congruent and all angles less than 90 degrees, this is an acute scalene triangle.

100

If the two lines are parallel are

angle2congangle6

 .Explain. 

Yes they are congruent since corresponding angles are congruent when lines parallel.

200

Are the following congruent? Explain

Yes. Since both triangles are right triangles, have a leg congruent, and share there hypotenuse (so congruent). The two triangles would be congruent by Hypotenuse Leg Congruency.

200

Draw an example of a obtuse equilateral triangle

cannot! equilateral has all 60 degree angles (always acute)

200

Find a line that is parallel and another line perpendicular to

y=2x-75

 that goes through the point (-2,3)

Parallel:  y=2x+7 

Perpendicular:  y=-1/2x+2 

300

Are the two triangles congruent? Explain:

Yes. Since they have a pair of parallel sides, we can say  angleBcongangleC since alternate interior angles congruent when lines parallel. Also,  angleBXAcongangleCXD since fertical angles are congruent. So the two triangles congruent by Angle Angle Side congruency.

300

Given

triangleZYWcongtriangleXER

 State all congruent parts and draw a diagram.

Congruent parts:

angleZcongangleX

angleYcongangleE

angleWcongangleR

ZYcongXE

YWcongER

ZWcongXR

300

Solve for x:

x=12

400

Are the triangles congruent if both 

triangleJZF

and

triangleQZX

are isosceles? Explain:

Yes, since isosceles  angleJcongangleF since base angles are congruent and  JZcongFZ by definition of isosceles. Also since  angleZQXcongangleZXQ we know that  angle1congangle2 since they are both linear pairs with  angleZQX and angleZXQ . So by Angle Angle Side congruency the triangles are congruent.

400

If 

triangleABCcongtriangleDEF

mangleD=20

mangleF=70

"Find":mangleB

"Then find": AC if BC=3 and AB=4

Since congruent triangles have congruent corresponding parts  mangleB=mangleE=90 . So since ABC is a right triangle, use pythagoreans theorem to find  AC=5 

400

Factor the quadratic:

7x^2 -13x-2

(7x+1)(x-2)

500

Given

triangleABC

 is isosceles. Is

triangleKK'McongtriangleLL'M

 ? Explain:

by Angle Side Angle Congruency

500

Create a coordinate proof:

()

500

Perform the following transformations on A(1,1), B(-2,-1), and C(5,-2):

1. Reflection over y=x

2. Rotation 90 degrees CCW about the origin

3. Dilation about the origin by a factor of 3

Answer