Answer:
1) 180 is a straight line, so 180 - 118 = <em>62</em>
2) 180 degrees are in a triangle, so 180 - (62) - 73 = <em>45</em>
3) 180 is a straight line, so 180 - 73 = 107. There are 180 degrees in a triangle, so 180 - 49 - 45 = <em>86</em>
7.79cm It is an equilateral triangle so it has 3 equal sides. That means each side is 9cm. <span>
Now draw a line from the top of the equilateral triangle to the base, and dividing it into two. You will have made two smaller triangles, with sides 9, 4.5, and h (the one you want to find).
A line drawn from the apex of an equilateral triangle to the midpoint of the base is perpendicular to the base, so you can use Pythagoras' Theorem!
4.5^2 + h^2 = 9^2
h = sqrt(9^2 - 4.5^2)
Therefore, the height is 7.79cm (2 decimal places)</span><span>
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