Answer:
Explanation:
add the 2 equations:
3x+18+4x+15
simplify:
7x+33
we know that all angles on a straight line is 180 degrees.
7x+33=180
solve that equation:
7x=147
x=21
from here substitute x=21 into both equations.
3x+18
3x=63
63+18=81
left angle is 81 degrees
4x+15
4x=84
84+15=99
right angle is 99 degrees
we can check this by adding them both: 99+81=180
its right as all angles on a straight line add to 180, which these do.
hope this helped