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This is my next Trigonometry question I am needed help on- I just want to be sure I've got it right, or if not, then the steps I need to take to get it right. Thank you.

This is my next Trigonometry question I am needed help on- I just want to be sure-example-1
User Bjorgum
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\bf cos(\theta)=\cfrac{3}{5}\cfrac{\leftarrow adjacent=a}{\leftarrow hypotenuse=c} \\\\\\ c^2=a^2+b^2\implies \pm√(c^2-a^2)=b\implies \pm√(5^2-3^2)=b \\\\\\ \pm√(16)=b\implies \pm4=b

so, plus or minus? well, the angle is in the 1st quadrant, and on that quadrant, both cosine and sine are positive, so 4 = b


\bf tan(\theta)=\cfrac{opposite}{adjacent}\implies tan(\theta)=\cfrac{4}{3}
User Matthew Moisen
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