PLEASE HELP. I need DE AND EF!!!
1 answer:
Answer:
DE = about 41.843 (rounded to nearest thousandth)
EF= 34.276 (rounded)
Step-by-step explanation:
For DE, we know that the shorter side (the opposite side) is 24, while the angle across form it is 35°. We can use trigonometry to figure this out. SinФ equals the opposite side (in this case, 24) divided by the hypotenuse. Set sinФ equal to a ratio of the sides like this:
sin(35) =
x represents the hypotenuse length, which we don't know; 35 is the angle measure. Next, isolate x so that the equation looks like this:
= x
You will need a calculator for the next part. (and make sure you're in degree mode!). evaluate sin(35) and divide 24 by that value. That is DE's length. DE = about 41.843 (rounded to nearest thousandth)
For EF, we can just use Pythagorean theorem now that we know the other sides' values.
EF^2 + 24^2 = DE^2
*a calculator might also be useful for this part.
EF= 34.276 (rounded)
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Answer:
Options (2) and (3)
Step-by-step explanation:
Let,
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=
=
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a =
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Options (2) and (3) are the correct options.