We are asked to solve for the measurement of the angle 2 in the given shape which is a rhombus. Since we already know that the opposite angles of a rhombus are congruent to each other which means that they have the same value. Such that in the attached document, the angle 1 is the same an equal to angle 3 while the angle 2 is equal to angle 4.
Angle 3 = 80° then angle 1 is also 80°
We know the total for all angles is 180°, hence we have it:
360° = ∠1 + ∠2 +∠3 +∠4
180° = 80 + ∠2 + 80 +∠4
180 - 160 = ∠2 + ∠4
20 = ∠2 + ∠4
10° = ∠2
10° = ∠4
The answer for angle 2 is equal to 10°.