Question

find the measure of the unknown angle in angle in each of the following.an angle marked with |_ is a right angle​.

pls ans please

Answer 1

Answer:

answer first one=

57 +42=99

180- 99

=81

unknown angle is 81

Answer 2

Answer:

understand this

In angle ∆ABC,

∆a +∆b+∆c=180

∆42+∆x+∆57=180

∆x+∆99=180

∆x=180-99

∆x=∆81

this is right answer of the question