You must convert point slope form to standard form in this problem. point= (h,k)
POINT SLOPE:
y-(-1)=(3/4)(x-2)
y+1=(3/4)x-(3/2)
y= (3/4)x-(5/2)
The function

is a parabola concave up, whose solutions are

from here, you can use the quadratic formula

to find that the solutions of the parabola are 
So, the parabola is positive if
(which wouldn't make sense in our case) or 
So, if Tanya caters 25 meals she breaks even, and starting with the 26th meal she will begin to profit.
1. 20 x 8 = 160 m
2.
January to November = 11 months.
11 flats are painted every year.
100 flats / 11 flats per year = 9 years + 1 month
the next time it will be painted is September 2019.