How do i solve this trig question??

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3 Answers

You use the definition of sine of an angle, in this case W, to solve this problem in almost a single step.

Explanation:

The definition of sine of an angle is:

sin(theta) = ("Opposite")/("Hypotenuse") where,

theta is the angle you're looking to solve,

Opposite is the measure of the side directly opposite of the angle

Hypotenuse is the side across form the 90 degree angle

Remember that this will only work for right triangles. A more complex version of this identity is used for non-right triangles.

Now, for your problem specifically, we take

sin(W) to equal your opposite side, 7, over divided by your hypotenuse, 8:

sin(W) = 7/8

IMPORTANT: Your calculator must be set to "Degrees" mode for this next part!

Take sin^-1 of both sides to solve for W and you get:

W = sin^-1(7/8) Plug that into your calculator and you get:

W = 61.04497563

Then applying the appropriate rounding for the problem you get:

W = 61.0

Mar 18, 2018

angleW=61.0^@

Explanation:

"Since VWX is a right triangle use "color(blue)"trig. ratio"

•color(white)(x)sin hatW="opposite"/"hypotenuse"=(VX)/(VW)=7/8

rArrangleW=sin^-1(7/8)=61.0^@

Mar 18, 2018

mangleW=61^@

Explanation:

Since this is a right triangle, we are able to use the tan, sin,and cos functions.

We know the lengths of the opposite side from angleW and the hypotenuse, so we will use the sin function.

sin angleW= "opposite"/"hypotenuse" rarr sin angleW = 7/8

Using your calculator, find the value of 7/8, which should be 0.875. The equation should now look like this:

sin angleW=0.875

Still using your calculator, hit 2nd and then hit sin, this will show you the measure of angle W. (You may not have a 2nd button in which case use "sin"^-1.)

angleW=61.045 rarr 61^@

Here are a couple things to remember when you see questions like this:

  1. Determine which side lengths you know so that you can decide which function to use (tan, sin, cos)
  2. When you have the form like the one that we had in this question (sin angleW=0.875) remember to hit 2nd and then the function. Or, depending on your calculator, you should use sin^-1, cos^-1, tan^-1 instead.