so... notice the picture below, the angle in the fourth quadrant
now... notice, the cosine is just the distance the angle makes with the x-axis
so... using the pythagorean theorem, get the opposite side, from that triangle, keeping in mind that, "y" is negative in the 4th quadrant
once you get "y", get any other trigonometry value you need :)
Answer:
x = 8
Step-by-step explanation:
Since < A and < B are vertical angles, then it means that they have the same measure.
Given that m < A = (3x - 21)°, and m < B = (2x - 13)°:
We can set up the following equation to solve for the value of x:
m < A = m < B
(3x - 21)° = (2x - 13)°
3x - 21 = 2x - 13
Subtract 2x from both sides:
3x - 2x - 21 = 2x - 2x - 13
x - 21 = -13
Add 21 to both sides to isolate and solve for the value of x:
x - 21 + 21 = -13 + 21
x = 8
We must verify if we have the correct value for x by plugging in 8 into the equality statement:
(3x - 21)° = (2x - 13)°
[3(8) - 21]° = [2(8) - 13]°
(24 - 21)° = (16 - 13)°
3° = 3° (True statement. This means that we have the correct value for x).
Therefore, the value of x = 8.
Please mark my answers as the Brainliest, if you find this solution helpful :)
