It is a horizontal line as there is no y-axis in its equation.
(x + 1) / 5 = (x + 5) / 7
cross multiply
(x +1) x 7 = 5 x (x + 5)
7x + 7 = 5x + 25
take the like terms to one side
7x - 5x = 25 - 7
2x = 18
divide by 2 to isolate x
2x / 2 = 18 / 2
x = 9
check:
9 + 1 / 5 = 9 + 5 / 7
10 / 5 = 14 / 7
2 = 2
Kelly will have enough time to finish before the guests arrive because 45+35 = 1 hour and 10 mins, which adds that with 11:45, it would be 12:55 when she finishes. Making it possible.