Answer:
x = 55°
Step-by-step explanation:
Parallel lines and transversals:
Corresponding angles: When a transversal cut two parallel lines, the angles on the same position(place) of the same side of the transversal are equal and they are called corresponding angles.
l // m and p is the transversal.
∠1 = x + 9 {Correpsonding angles}
2x + 6 + x + 9 = 180° {Linear pair}
2x + x + 6 + 9 = 180
Combine like terms,
3x + 15 = 180
Subtract 15 from both sides,
3x = 180 - 15
3x = 165
Divide both sides by 3,
x = 165 ÷ 3
[tex]\boxed{\bf x = 55^\circ}[/tex]
