Answer:

Step-by-step explanation:

Collect like terms
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Calculate
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Hope I helped!
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Answer:
60°
Step-by-step explanation:
Total angle measurement for a triangle is 180°
Equilateral triangle measures 60 on all angles. (60 + 60 + 60 = 180°)
This triangle is equilateral so it's angle is 60°.
Why is it equilateral? Because all sides of the triangle are equal (10 on all sides).
Hope this helps
The number of smaller triangles along one side of the larger triangle is the square root of the total number of triangles. The perimeter of the large triangle is ...
3*(2 cm)*√121 = 66 cm