Question

The equation y = 55x + 85 describes the amount of money a plumber charges, where y is the total amount he charges and x is the number of hours he works. The table shows the total amount of money an electrician charges.

How much does each charge per hour?

Number of hours worked 1 2 4 7
Total amount charged 115 180 310 505

The plumber charges $ per hour.
The electrician charges $ per hour.

Answer 1

Does the plumber charge $55?

Answer 2

and the electrician $85?

Answer 3

for the plumber
y = 55x + 85
for 1 hour the charge is 55(x) = 55(1) = 55

Answer 4

does the electrician charge $60, $65 or $85?

Answer 5

for the electrician
y = ax + z
115 = a + z
180 = 2a + z where a is charge per hour and z = standard charegr

subtract first equation for the second
a = 180 - 115 = 65

electriciam charges 65 dollars per hour

Answer 6

Okay! Thank You! ^.^

Answer 7

yw