Question

A company discovers that it costs $18 to produce 2 calculators, $66 to produce 4 calculators, and $450 to produce 10 calculators. Using quadratic functions, find the total cost of producing 8 calculators.

Answer 1

yes. i just checked over it again to make sure.

Answer 2

(2,18) (4,66) (10,450)

b = (18-66)(100-4) + (450-18)(16-4)
------------------------------
(2-4)(100-4) + (10-2)(16-4)

Answer 3

b = (-48)(96) + (432)(12)
-------------------
(-2)(96) + (8)(12)

Answer 4

b = -4608 + 5184 576
------------- = ---- = -6
-192 + 96 -96

b = -6

Answer 5

(2,18) (4,66) (10,450)

a = (66-18) (4-2)(6)
------- - -----
(16-4) (16-4)

a = 48 12 36
---- - ----- = ----- = 3
12 12 12

a = 3; b = -6

Answer 6

c = 18 - 4(3) - 2(-6)

c = 18 -12 +12 = 18

3x^2 -6x +18 let me double check that

Answer 7

i really have no idea how you remember all those steps!! this would so much easier with a graphing calc!

Answer 8

lol... thats ok, i have to redo it :) im gonna work it out on the paper, itll just be easier for me :)

Answer 9

Graphing calculators are for babies.

Answer 10

graphing calculators are for people who really don't like math & like to take the easy way to get it done with faster.

Answer 11

No, people who want to do it the easy way use this:
http://www.quickmath.com/webMathematica3/quickmath/equations/solve/advanced.jsp#v1=4a+%2B+2b+%2B+c+%3D+18%0A16a+%2B+4b+%2B+c+%3D+66%0A100a+%2B+10b+%2B+c+%3D+450&v2=a%0Ab%0Ac

Answer 12

well if i would've found that or someone would've gave me the site, i would use it. but they didn't so i couldn't.

Answer 13

amistre... ready?

Answer 14

its 1:45 am here and my brain aint behaving itself ....sorry racer, maybe tomorrow :)

Answer 15

this is the last question & i'll be done..

Answer 16

Do you want me to do it?

Answer 17

well it's too late now. i thought i would be able to figure out the answer from what she gave me. but it was wrong & i could only miss 1 out of 5.

Answer 18

OK... later

Answer 19

thanks though. guess i'll try again tomorrow.

Answer 20

After some sleep, I see where I went wrong :)

b=-6 is good, but when I used it down here I made it "+6".....which of course threw off my numbers....

(2,18) (4,66) (10,450)

a = (66-18) (4-2)(-6) <-- right there
------- - -----
(16-4) (16-4)

a = 48 -12 60
---- - ----- = ----- = 5
12 12 12

a = 5; b = -6 ; now THOSE are the right numers :)

Answer 21

c = 18 -4(a) - 2(b)

c = 18 - 4(5) - 2(-6)

c = 18 -20 +12

c = 30 - 20

c = 10

y = 5x^2 -6x +10 is the good equations.

y = 5(8)^2 -6(8) +10

y = 5(64) -48 +10

y = 320 -38

y = 282

the cost of 8 calculator costs $282