Which expression can be used to find X?
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Answer: a.
Step-by-step explanation:
If we use Toa from the mnemonic SohCahToa, which means tan(theta) = opp/adj, we can solve for adj (which is x in this case) to get
opp/tan(theta) = adj, or in this case 10/tan(38) which is a. in this case.