Question

Can someone please help??? Any one of them would be fine.

Answer 1

Alright...so for part A...we know that there is always going to be a constant monthly charge of 20 dollars...we also know they will be charged an additional 20 for 250 text, and also there will be a 5 cent a minute charge...

so what do we have?

5 cents per minute? we don't know how many minutes will be used...so this is a variable...something like .05k

and 2 constant charges...20 + 20...

so plan A would look something like .05k + 40

Answer 2

Part B...we want to know when the charges will be the same...also known as...when will these equations be the same number?

Well, to find that...make these 2 equations equal each other and solve for 'x'

\[\large .05x + 40 = .10(x - 100) + 35\]

Answer 3

Part C...you can graph the plan A one...just a standard slope intercept form...

for plan B however...simplify the equation they give you to look like slope intercept form
* y = mx + b *

Answer 4

And finally Part D ...set each equation = to 75 and see which 'x' would be bigger...

\[\large.05x + 40 = 75\]
\[\large .10(x - 100) + 35 = 75\]

and just solve for 'x' in each case