Edxcel Pure maths modelling question

[lime nimbus]

Which part do u need help with

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a and b please

i attempted a it didnt look right so i couldnt even do b

[lime nimbus]

Ok so it’s a linear model so it’ll be of the form V = md + c and we just need to find m and c

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ohh

okk

[lime nimbus]

Do u understand how to find them now

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for me i got v=-8d-240

[lime nimbus]

Did you sub in the values they gave

I think it should be V = ||50 - d/8||

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oh

can u show me ur working out pls

if thats okay

[lime nimbus]

We know two points are (80, 40) and (200, 25)

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yes

[lime nimbus]

So if we sub these in for V and d we get 2 equations in terms of m and c

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yess

[lime nimbus]

Then just subtract one from the other to eliminate c, find m and then sub it back in to get c

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oh okk thanku soo much now i get it

[lime nimbus]

Np

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how would u do b

do i have to sub in 0 for the initial volome

[lime nimbus]

So initial volume would mean d=0

Ye

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yess

[lime nimbus]

So it would just be the value of c

For the second part, it will stop moving once V = 0

So we make V =0 and solve for d

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yess thanks alottt. for c what could my evaluation be

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yess thank alott

[lime nimbus]

Maybe we have to find the answers for part b first and then evaluate

Idrk about evaluating models I’ve never done it before but maybe it’ll make more sense once you’ve find answers to b

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yes thanks alott for ur helpp