Business and finance. The cost of producing a number of items x is given by

C = mx + b, in which b is the fixed cost and m is the variable cost (the cost of producing one more item).
(a) If the fixed cost is $40 and the variable cost is $10, write the cost equation.
would the equation be
C=10x+40

(b) Graph the cost equation.
I am not sure what I am suppose to graph here

(c) The revenue generated from the sale of x items is given by R=50x. Graph the
revenue equation on the same set of axes as the cost equation.

I am also stuck here I feel like i have missed something while i am reading this question over and over please help

(d) How many items must be produced for the revenue to equal the cost (the
break-even point)?

a) yes
b) find any two points with your equation
e.g. let x = 0, then C=40
let x=10, then C = 140
Now plot (0,40) and (10,140) by using a suitable scale for your x and C axes.

c) since both C and R are in dollars you can use the same vertical axis
do the same as in b)

d) you want R = C, but you have expressions for both
so 50x = 10x + 40

solve, you should be able to do this in your head by just looking at that equation.

so on d i need to
50*1=10*1+40
50=50

then i need to put this in my graph
x=1
r=50

For part (d), you are correct in setting up the equation 50x = 10x + 40. To find the break-even point, you want to solve for x. Here's how:

50x = 10x + 40

Subtract 10x from both sides to isolate the x term:

50x - 10x = 40

Combine like terms:

40x = 40

Divide both sides by 40 to solve for x:

x = 1

So, the break-even point occurs when 1 item is produced. You can plot this point on the graph.