$18.00 breakfast; 7% tip

1.26

Step-by-step explanation:

18 x .07 = 1.26

(3,285)(6,510)
slope = (510 - 285) / (6 - 3) = 225/3 = 75

y = mx + b
slope(m) = 75
use either of ur points...(3,285)...x = 3 and y = 285
now we sub and find b, the y int
285 = 75(3) + b
285 = 225 + b
285 - 225 = b
60 = b

equation is : y = 75x + 60...but we need it in standard form..

y = 75x + 60
-75x + y = 60
75x - y = -60 <== standard form

function notation is : f(x) = 75x + 60

x axis labeled days, and y axis labeled total costnot to sure of the intervals...sorry.
y = 75x + 60slope = 75...y int = (0,60)x int = (- 4/5,0)