A 180 degree angle (straight line) is formed by two adjacent angles. One angle has a measure of (2x+3) degree and the other has a measure of (x-6) degree. What are the measures of the two angles that make up the straight line?
A. 121 degree and 59 degree
B. 125 degree and 55 degree
C. 129 degree and 51 degree
D. 186 degree and 88 degree
The sum of the two angles that make up a straight line is always 180 degrees.
Therefore, we can set up the equation:
(2x+3) + (x-6) = 180
Combining like terms, we have:
3x - 3 = 180
Adding 3 to both sides, we have:
3x = 183
Dividing both sides by 3, we have:
x = 61
So, substitute the value of x back into the expressions for the angles:
1st angle: 2x+3 = 2(61)+3 = 125 degrees
2nd angle: x-6 = 61-6 = 55 degrees
Therefore, the measures of the two angles that make up the straight line are 125 degrees and 55 degrees.
The answer is B. 125 degree and 55 degree.