3x + 6 = 48 (alternate angles are equal)
- 6
3x. = 42
÷3
x = 14 degrees
180-48 - 2y + 5y-9 =180
123 + 3y = 180
-123
3y = 57
÷3
y = 19 degrees
Explanation:
To find the last angle on the top straight line, do:
180 - (the 2 given angles).
So, 180 - (3x + 16, which is 48 due to alternate angles being equal). Then, minus the 2y.
(180 - 48 - 2y) & simplify => 132 - 2y
This gives you the equation for the missing angle on our top straight line.
Thus, co-interior angles add to 180. So, we add the new equation (132 - 2y) to 5y - 9.
Simplify
=> 123 + 3y (because - 2+5 =3)
and put it equal to 180. Solve for y
Hope this helps!
