Answers:
angle2 = 160 degrees
angle3 = 10 degrees
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Step-by-step explanation:
The two triangles are congruent. We can prove this using SSS. The upper triangle is a mirrored copy of the lower triangle.
Since angle1 = 160 degrees, this means angle2 = 160 also. This is because the corresponding pieces of congruent triangles match up. Or you could use the second part of the hint which says "Opposite angles in a rhombus are congruent".
Let x be the measure of angle 3. For either isosceles triangle, it has congruent base angles measured x degrees. They add to the 160 degrees mentioned earlier to get a total of 180.
160+x+x = 180
2x+160 = 180
2x = 180-160
2x = 20
x = 20/2
x = 10
Angle 3 is 10 degrees.