In triangle abc, if an exterior angle drawn at vertex c
measures 45, then angle b
a. must be an obtuse angle
b. must be a right angle
c. may be either an obtuse angle or an acute angle
d. must be an acute angle
question 2
in triangle abc, the measure of an exterior angle at b is 5 more
than twice the measure of zc. if m2c = 65, what is
mza?
a.45
b.70
c.110
d.135

Part 1) Option D. must be an acute angle

Part 2) m∠A=70°

Step-by-step explanation:

Part 1) In triangle ABC, if an exterior angle drawn at vertex C  measures 45, then angle B...

we know that

An exterior angle of a triangle is equal to the sum of the opposite interior angles

so

The measure of an exterior angle at C is equal to the sum of the interior angles at A and B

we have that

45°=m∠A+m∠B

therefore

m∠B < 90°

Angle B must be an acute angle

Part 2)

we know that

An exterior angle of a triangle is equal to the sum of the opposite interior angles

so

The measure of an exterior angle at B is equal to the sum of the interior angles at A and C

m∠A+m∠C=2m∠C+5

m∠C=m∠A-5 > equation A

m∠C=65° > equation B

substitute equation B in equation A

65°=m∠A-5

m∠A=(65+5)°=70°

∠lno ≅ ∠lnm

∠oln ≅ ∠mln

step-by-step explanation:

given   that triangle lno is congruent to triangle lnm.

we have to fill up the blanks in the given question.

according to above order of congruency   kept in mind we can say that

∠lno ≅ ∠lnm

∠oln ≅ ∠mln

ln ≅ ln due to common in both.

hence, by sas congruency,

the side angle side rule   states that if two sides and the included angle of one triangle are congruent to another triangle, then these two triangles are congruent.