Question

Help me pls pls pls pls pls

Answer 1

cost = 170 × mass of coal + 60

Explanation:

the graph is a straight line and is therefore linear with equation

y = mx + c ( m is the slope and c the y- intercept )

calculate the slope m , using the slope formula

m =
`(y_(2)-y_(1) )/(x_(2)-x_(1) )`

let (x₁, y₁ ) = (0, 60) and (x₂, y₂ ) = (2, 400) ← 2 points on the line

substitute these values into the formula for m

m =
`(400-60)/(2-0)` =
`(340)/(2)` = 170

the line intersects the y- axis at (0, 60 ) , then c = 60

y = 170x + 60

the y- axis is cost and the x- axis is mass of coal

Then the formula is

cost = 170 × mass of coal + 60

Answer 2

m = (140 - 60)/.5 = 80/.5 = 160

y = 160x + 60

cost = (160 × mass of coal) + 60