Answer:
y = 40x + 30
Step-by-step explanation:
The equation for a linear function is given by:
y = mx + b;
where y and x are variables, m is the slope or rate of change of the function and b is the initial value of y at x = 0 (that is y intercept).
Let y represent the total cost and x represent the number of hours worked.
The electrician charges 110 after 2 hours of work and 190 for 4 hours of work.
Representing in coordinate form as (x, y) we get:
(2, 110) and (4, 190)
The equation of the function can be gotten using the formula:
[tex]y-y_1=\frac{y_2-y_1}{x_2-x_1}(x-x_1)[/tex]
Therefore:
[tex]y-110=\frac{190-110}{4-2}(x-2)\\\\y-110=40(x-2)\\\\y-110=40x-80\\\\y=40x-80+110\\\\y=40x+30[/tex]
