Answer:
s = 17
Step-by-step explanation:
To solve, set the expressions equal to each other.
77 = (4s+9)
You want to get s by itself, so subtract the 9 from both sides.
77 = (4s+9)°
-9 -9
68 = (4s)
Divide by 4
68/4 = 4/4s
68/4 = 17
Alternate Interior Angles are always equal to each other.
