Answer:
C
Step-by-step explanation:
For plumber A : y = 100 + 30x
For plumber B :
Let the total charge be y
Initial charge be x
Hourly rate be za
For total price = 105 in 1hr
105 = x + a ........(1)
For 160 total charge in 2hrs
160 = x + 2a .........(2)
Substracting (1) from (2)
160 - 105 = 2a - a
55 = a
Substituting a = 55 in (1)
105 = x + a
105 = x + 55
x = 105 - 55
x = 50
:- equation for total charge is
y = 50 + 55a
