Writing equations and calculating cost based on a graph

[Kirito123]

So if it is 11, would that mean that y = 1.25x + 11?

 

[member 587159]

So if it is 11, would that mean that y = 1.25x + 11?

You can verify whether you are correct by choosing a random point and fill the x and y in in the equation. When you get something like '3 = 3', you are correct. Do you get something like '3=4', you made a mistake. Every single point of the line is given by this equation (if correct) .

 

[Kirito123]

No I am wrong then cause if i plug in x and y as 2 for example i would get like 2 = 15 (near 15).

 

[SammyS]

And the question Math_IQ asks is: "What do you get for b ?"

(I think you already have it.)

No I am wrong then cause if i plug in x and y as 2 for example i would get like 2 = 15 (near 15).

2×1.25 = 2.50

2.50 +11.00 = 13.50

Looks good to me !

 

[Kirito123]

O i thought i was wrong cause if i put 3 = 1.25(3) + 11 it doesn't make 3 =3 or did i not understand what math_qed mean't.

 

[Kirito123]

So if I am correct should i just use that formula to solve for the graph i made?

 

[SammyS]

So if I am correct should i just use that formula to solve for the graph i made?

Yes, make a chart for prices all the way from 0 extra letters all the way to 12 extra letters. When finished, make sure it agrees with the graph.

 

[Kirito123]

ok

 

[Kirito123]

Yes that formula is right. i tried it with 0 , 1 , 2, and 3 and i got the same answer as shown on the graph. I think the whole reason i got it wrong was because i didn't look a the graph closely. i think i can do the rest now. Thx a lot :)

 

[SammyS]

Try larger values of x.

Check a larger range of the graph.

x=6, 8, 9,12 .

 

[Kirito123]

ok i will

 

[Kirito123]

Ok i tested it out for 6 and other numbers and i got the right answer, (srry for the late reply). But anyway that proves the formula is right and THX SO MUCH.

if I am wrong pls correct me. Formula : y = 1.25x + 11

 

[member 587159]

Ok i tested it out for 6 and other numbers and i got the right answer, (srry for the late reply). But anyway that proves the formula is right and THX SO MUCH.

if I am wrong pls correct me. Formula : y = 1.25x + 11

Seems good.

 

[Kirito123]

thank you again.