Assuming that the cost per minute is the same for both months and the plan fee is the same, you can use y=mx+b for this
y is the cost of the phone plan, x is the cost per minute and b is the start cost.
so 19.41=25x+b for the first month
and 45.65=380x+b for the second month
solve both for b you get:
19.41-25x=b and 45.65-380x=b. from this we get
19.41-25x=45.65-380x
solve for x
328x=26.24 and x=0.08
this means the cost per minute is 0.08c/min (answer A)
rewrite the equation to calculate b, and where this time, the x is the number of minutes talked.
y=0.08x+b and plug in one of the two months
45.65=0.08 * 380 + b
Solve for b and b is 15.25
so the final equation is
y=0.08x+15.25 (answer B)
Konichiwa~! My name is Zalgo and I am here to help you out today. If f were to equal -3, first we need to put -3 into the equation. It would look like "f(-3)=x^2". The answer to that equation is 9.
I hope that this helps! :T
"Stay Brainly and stay proud!" - Zalgo
4 people x 45 minutes = 180 minutes total to paint 5 walls
180/5 = 36 minutes of man work per wall
36 * 4 walls = 144 total minutes
144/6 people = 24 minutes total
