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Find the size of angle XYZ. Give your answer to 1 decimal place.

Find the size of angle XYZ. Give your answer to 1 decimal place.-example-1
User Yavanosta
by
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2 Answers

5 votes

ANSWER: 54.3

Explanation:

1. Label each side of the Triangle

Using the SOH CAH TOA method we can label zy as H (the longest line is always H). We can label xz as O (it is opposite the angle). We can label xy as A (it's the remaining side).

2. Cross out the 'useless' side

Now, we need to cross out the label which doesn't have an appointed piece of information to it. Meaning that A will remain as it labels 7cm. H will also remain as it labels the angle. O does not label anything and so we can cross it out.

3. Decide which method is correct

We are using the SOH CAH TOA method, this means we can either use SOH, CAH, or TOA to solve the problem. We know which method to use by seeing which of them does not contain the letter we crossed out. CAH does not contain O so it is the correct method.

4. Know the formula

Now we will use the formula of our found method. CAH begins with C and so does Cos. Therefore, Cos is our formula.

Cos( ) = A/H

5. Substitute in your numbers

Then, we will put in our numbers into the formula. The first slot we must fill in is within the brackets. Usually the angle goes inside of the brackets during trigonometry but we obviously do not know it. This means we will use 'x' inside of the brackets. Our formula now looks like this:

Cos(x)

Substitute in A and H. A will be the information appointed to the side we labelled A. H will be the information appointed to the side we labelled H.

Our formula will look like this:

Cos(x) = 7/12

6. Reverse it and calculate

Now we need to input an equation into our calculator. I don't know why but we will need to reverse our previous formula and type it into the calculator as:

cos-^1(7/12)

The result should say 54.31466529.

7. Round

Now we will round it by 1 decimal place. To do this we need to look at the number next to 3, it is not 5 or above 5. This means we will not round up,

our answer is 54.3 degrees.

User Aaron McAdam
by
5.2k points
3 votes

Answer:

45

Explanation:

Because this is a triangle all angles must add up to 180. so we already know 90 so 180-90=90 and 90/2 = 45. Hope this helps

User RAAAAM
by
5.1k points