Problem 54 of 7
Find the missing angle from equal sine/cosine expressions cos(y°)=sin(55°).
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set angles complementary.
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Set sine angle and cosine angle complementary when using cofunction equality in acute-angle context.
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Your answer is equivalent to the expected form.
Walkthrough
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1. Identify the sine angle expression and cosine angle expression.
2. Set their sum equal to 90 degrees.
3. Solve the linear equation.
Use the worked steps, then substitute the final answer back into the original relationship to confirm it satisfies the prompt.
Setting angle expressions equal for sine-cosine cofunction equations.