Answer:
see explanation
Step-by-step explanation:
Using the sine and cosine ratios in the right triangle and the exact values
sin60° = and cos60° = , then
sin60° = = = = ( cross- multiply )
2BC = 10 ( divide both sides by 2 )
BC = 5
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cos60° = = = = ( cross- multiply )
2AB = 10 ( divide both sides by 2 )
AB = 5