If angle 3 = 81, what is angle 4?

99 degrees

Step-by-step explanation:

Angle 3 and 4 added together is 180 degrees since it is a straight line.

if you know angle 3 is 81 degrees, then angle 4=180-81=99

99 is the measure of angle 4

Step-by-step explanation:

Two parralel lines cut by a transversal.

This is all you gotta remember

Alternate interior angles (4 and 6, 3 and 5) are congruent (equal)

Altenrate exterior angles (1 and 7, 2 and 8) are congruent (equal)

Corresponding angles (2 and 6, 3 and 7, 1 and 5, 4 and 8) are congruent (equal)

Same side interior angles (3 and 6, 4 and 5) are supplementary (equal to 180 if added up)

Same side exterior angles, (2 and 7, 1 and 8) are supplementary (Equal to 180 if added up)

Same line, opposite transversal (4 and 3, 5 and 6, 8 and 7, 1 and 2) are also supplementary.

step-by-step explanation: