Answer: m ∡ x = 23° .
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Using the mnemonic: "SOH CAH TOA" .
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Let's use "SOH" ; that is: "sin x = opposite/hypotenuse" ; since we have the values of "opposite" and "hypotenuse" (with respect to "angle x").
sin x = opposite / hypotenuse = (4.5) / (11.75) = 18/47 = 0.3829787234042553 ;
→ Solve for "x" by taking the "arcsin" ("inverse sine") of each side (use calculator):
→ arc sin x = arc sin (18/47) = 22.518314130871 ;
→ Round to the nearest degree; 22.518 → rounds to: 23 .
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→ m ∡ x = 23° .
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