Answer:
6a. 13.5m
6b. 12.4m
Explanation:
We can use trig identities to solve these problems because each triangle is a right triangle.
6a. Find the measure of the hypotenuse.
Using the angle in the top corner, which is defined as 66 degrees and its adjacent side, we can find the hypotenuse. Remember that the hypotenuse is the longest side, which in this case would be AB. The adjacent side is the side next to the angle that is not the hypotenuse, in this case it would be AC, which is shown to be 5.5m.
The trig identity cos(x) is defined as adjacent/hypotenuse, or the value of the adjacent side divided by the value of the hypotenuse, where x is the degrees of the angle.
So we can set up the equation:
cos(x)=adj/hyp
If we know that x=66 (the degree of the angle) and adj=5.5m, we can substitute this into the equation. Let c represent the hypotenuse.
cos(66)=5.5/c
Then we can multiply by c:
c*cos(66)=5.5
Then divide by cos(66):
c=5.5/cos(66)
Use a calculator to estimate that c approximately equals 13.5m when rounded to the nearest tenth (remember to use degree mode because our angle is measured in degrees).
6b. Find the measure of side a.
Side a is the side opposite to angle A. This can also be known as side CB or the bottom of the triangle.
Method 1: Use trig identity tan(x)tan(x)=opp/adj
Remember x=66 and adj=5.5m. Let a represent the opposite side. Plug in these values into the equation:
tan(66)=a/5.5
Multiply both sides by 5.5:
a=tan(66)*5.5
Use a calculator to estimate that a approximately equals 12.4m when rounded to the nearest tenth (remember to use degree mode because our angle is measured in degrees).
Method 2 (I would recommend method 1, however because you are basing this answer off of the first answer, and in a test or a quiz, you might not be sure if your first answer was correct):
Use Pythagorean Theorem:
a^2+b^2=c^2
c, or the hypotenuse is 13.5m as found in out last problem, and b, the adjacent side is 5.5m which was a given. Substitute these values into the equation:
a^2+5.5^2=13.5^2
a^2+30.25=182.25
a^2=152a=sqrt(152) which rounds to 12.3m, which is almost the same as Method 1, however our answers are different because we used a rounded value of b, rather than the approximate.