# trigonometry

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given triangle ABC with AB=7cm, BC=8cm and AC=9cm calculate
1. the size of the largest angle
2. the area of the triangle

• trigonometry -

1.
the largest angle is opposite the largest side, so set your cosine equation up this way:

9^2 = 7^2 + 8^2 - 2(7)(8)cosØ

2.
once you have that angles use the area formula
area = (1/2)(a)(b)sinØ , where Ø is the contained angle.

• trigonometry -

Find the a triangle whose sides are 7cm,8cm,and 9cm

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