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# GCSE Question? Genius need please? watch

1. Heres the Q:

p = total cost

n = no. of discs

p = a + bn

a and b are constants

cost of making 1000 discs is £58000
cost of making 2000 discs is £64000

calculate values a and b

ANY ONE KNOW HOW TO DO THIS AS THIS IS CONFUSING ME VERY MUCH - please can sum1 supply steps for this. thanx.
2. Put the vaules of p and n into the equations and you will get 2 equations.

To find a and b you should do simultaneous equations, to get rid of one of the unknowns and then will be able to find the remaining unknown. Then put that value into one of the other equations to find the other unknown.

Hope this helps
3. I have tried this but when I get the values and test them they come out wrong so can someone do it please and I can learn it by example?
4. p = total cost

n = no. of discs

p = a + bn

a and b are constants

cost of making 1000 discs is £58000
cost of making 2000 discs is £64000

calculate values a and b

p = a + bn

58000 = a + 1000b
64000 = a + 2000b

Take 1 from 2,

64000 - 58000 = 2000b - 1000b
6000 = 1000b
b = 6

58000 = a + 6000
a = 52000
5. 58000=a+1000b
64000=a+2000b

116000=2a+4000b (x2)
64000=a+2000b

subtract eq. 2 from eq.1

a=52000

sub a

58000=52000+1000b
6000=1000b
b=6
6. Dam, I was beaten to it!
7. aaaaaahhhhh I see now . thanx alot people! realy apreciat it

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