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Find BC, Round to the nearest tenth

Find BC, Round to the nearest tenth-example-1
User Bricky
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1 Answer

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Given:

Given that the measure of ∠A is 74°

The length of side b is b = 6.

The length of side c is c = 5.

The length of side BC is a.

We need to determine the value of BC.

Value of BC:

The value of BC can be determined using the law of cosine formula.

Thus, we have;


a^2=b^2+c^2-2bc \ cos (A)

Substituting b = 6, c = 5 and ∠A = 74°, we get;


a^2=6^2+5^2-2(6)(5) \ cos \ 74^(\circ)


a^2=36+25-2(30)(0.28)


a^2=36+25-16.8


a^2=44.2


a=6.6

Thus, the length of BC is 6.6 units.

User Nvirth
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