I am really stuck someone help
Find the value of x. Round to the nearest tenth. The diagram is not drawn to scale.
Trigonometric functions are Sin, Cos, and Tan defined as: Sin=opposite/hypotenuse Cos=adjacent/hypotenuse Tan=opposite/adjacent Which of these three is best suited for the diagram? (which pieces do you know?)
sin?
Cos, because we know the length of the leg adjacent to our angle(11) and we want to find the hypotenuse. So to solve this we setup the problem as follows: \[\cos(24)=\frac{11}{x}\]
then we solve for x, right?...
Yeah, we move x over to the other side by multiplying both sides by x. What happens when you evaluate: \[x(\cos(24))=(\frac{11}{x})*x\]
Yes, but be careful when multiplying trig functions. cos(24x) is very different from cos(24)*x or x*cos(24). So we have x*cos(24)=11. How do we get x by itself?
Multiply what by both sides? we have \[x*\cos(24)=11\] How do get x by itself?
What should we divide by?
24 is a part of the cos function, so they're tied together. Divide by cos(24) and what do you end up with?
Not quite. \[\frac{1}{\cos(24)}*x*\cos(24)=11*\frac{1}{\cos(24)}\]
It's okay. What happens when we simplify that expression? Can we cancel anything out?
Yes! Exactly. The cos(24) cancels out on the left leaving us with x=11/cos(24).
Mmhmm. If you're allowed a calculator or you're asked to give an actual number, just evaluate in your calculator and you get 12.04, rounded. If you're just asked to find x, I would say leave it exact in the form of 11/cos(24)
Yeah, just post another question and tag me in a comment.
New question. Where it says "ask a question..."
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