Answer:
y = 7
Step-by-step explanation:
First, find the value of x.
[tex] (12x + 9) + (8x + 11) = 180 [/tex] (linear pair)
Solve for x
[tex] 12x + 9 + 8x + 11 = 180 [/tex]
Collect like terms
[tex] 12x + 8x + 9 + 11 = 180 [/tex]
[tex] 20x + 20 = 180 [/tex]
Subtract 20 from both sides
[tex] 20x + 20 - 20 = 180 - 20 [/tex]
[tex] 20x = 160 [/tex]
Divide both sides by 20
[tex] \frac{20x}{20} = \frac{160}{20} [/tex]
[tex] x = 8 [/tex]
Thus,
[tex] (12x + 9) = (14y + 7) [/tex] (vertical angles)
Plug in the value of x, and solve for y
[tex] 12(8) + 9 = 14y + 7 [/tex]
[tex] 96 + 9 = 14y + 7 [/tex]
[tex] 105 = 14y + 7 [/tex]
Subtract 7 from each side
[tex] 105 - 7 = 14y + 7 - 7 [/tex]
[tex] 98 = 14y [/tex]
Divide both sides by 14
[tex] \frac{98}{14} = \frac{14y}{14} [/tex]
[tex] 7 = y [/tex]
