Answer: All four angles (angle1,2,3,4) are 30 degrees each
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Explanation:
A rhombus has all four sides that are the same length. Think of a square, but we don't necessarily need to have all four angles be 90 degrees (as the diagram indicates).
Focus on triangle MNP. We have N = 120 degrees. We also know that MN = NP due to the fact all four sides of a rhombus are the same length.
This immediately leads to triangle MNP being isosceles. The base angles opposite the congruent sides are congruent angles. So angle 1 and angle 3 are the same measure. For triangle MNP, angle M and angle P are the same.
Let's find the missing angle
M+N+P = 180 ... angles of a triangle add to 180
M+120+M = 180 ... plug in N = 120, replace P with M
2M+120 = 180
2M = 180-120 ... subtracting 120 from both sides
2M = 60
M = 60/2 .... dividing both sides by 2
M = 30
So N is also 30 degrees
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We've found that both angle 1 and angle 3 are 30 degrees each.
Any rhombus is a parallelogram, which means that angles 1 and 4 are congruent alternate interior angles. Similarly, angles 2 and 3 are the other pair of alternate interior angles.
Therefore, we can say
angle 1 = angle 4 = 30 degrees
angle 2 = angle 3 = 30 degrees
