Respuesta :

Angle (6) + Angle (7) = 180

Angle (6) + 57 = 180

Angle (6) = 180 - 57

Angle (6) = 123

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Angle (6) = Angle (8)

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Therefore:

Angle (8) = 123 degrees

Answer: The measure of angle 8 is  123° .

Step-by-step explanation:

Since we have given that

m∠7 = 57°

we have two lines intersecting each other at one point forming angles ∠7, ∠8, ∠5, ∠6.

So, Relation between ∠7 and ∠8 is linear pair.

And we know that ,

[tex]\angle 7+\angle 8=180\textdegree\\\\57\textdegree+\angle 8=180\textdegree\\\\\angle 8=180\textdegree-57\textdegree\\\\\angle 8=123\textdegree[/tex]

Hence, the measure of angle 8 is  123° .