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Can anyone show the solution to this problem?

x-2py=-3
3x-2y+q=-4
Are simultaneous equations where p and q are constants.
The solution to these simultaneous equations is x=1,y=q. Find the values of p and q.

Reply 1

Muttley79

Original post by Farhan01

x-2py=-3
3x-2y+q=-4
Are simultaneous equations where p and q are constants.
The solution to these simultaneous equations is x=1,y=q. Find the values of p and q.

x-2py=-3
3x-2y+q=-4 rearrange this to 3x - 2y = -4 - q

How do we get the same x coefficient in the two equations?

Reply 2

username963570

Replace each 'x' term with just '1' (essentially subbing in x=1) and do the same for the y's (i.e. replace the y's with q's) and then solve for p and q. I don't really know how far you got into this so can't give any more specific advice.

Reply 3

areeja1510

I think I have a solution:
substitute your x and y values so the equations become

1-2pq=-3
3-2q+q=-4 which then becomes 3-q=-4 when the q values are simplified

You would then solve this to find that q=7 and substitue this value into the other equation.

the other equation would then become 1-14p=-3
14p=4 so that means that p=4/14

Reply 4

Turquaz

Original post by Farhan01

x-2py=-3
3x-2y+q=-4
Are simultaneous equations where p and q are constants.
The solution to these simultaneous equations is x=1,y=q. Find the values of p and q.

Funny the world's best mathematician is asking help on TSR.

Reply 5

Farhan01

Original post by areeja1510

Well, to be honest, I did this way and got the same answer. However, the answer in my textbook is p=2 and q=-3
A-Levels are such a pain! Even the simplest problems are twisted :'(

Reply 6

Farhan01

Original post by Fas

Already did that but the answers don't match with that of my textbook. Can you show me the solution? the answers are p=2 and q=-3

Reply 7

Farhan01

Original post by Turquaz

Funny the world's best mathematician is asking help on TSR.

Do you have any solution for this bro? A-Level maths are killing me!

Reply 8

ChrisSharman

I got q as 7 and p as 2/7. Just wanna be right before I help :smile:

Reply 9

Farhan01

Original post by ChrisSharman

I got q as 7 and p as 2/7. Just wanna be right before I help :smile:

I got the same answers though but the answer in my textbook is p=2 and q=-3

Reply 10

Iahmed512

Original post by Farhan01

I got the same answers though but the answer in my textbook is p=2 and q=-3

You, I and others got the same answer so it is correct and the textbook is probably wrong. Which is especially more likely if it is one of the new spec ones directly from the exam board as they tend to have more mistakes

Reply 11

mahfuzx10

The solution in the book is definitely incorrect because the second equation is only dependent on q and there can only be one point such that (1,q) lies on 3x-2y+q=-4. You can try and experiment by changing the value of q and graphing the equation each time. You will see that the point (1,q) only lies on the line when q=7.

Reply 12

Farhan01

Thank you all. You guys are right, the answers in my textbook are definitely wrong.
A-Levels are already tough and on top of that, the textbooks aren't reliable. Really feel hopeless :'(

Reply 13

Iahmed512

Original post by Farhan01

Thank you all. You guys are right, the answers in my textbook are definitely wrong.
A-Levels are already tough and on top of that, the textbooks aren't reliable. Really feel hopeless :'(

Yeah that's why my teacher said the school didn't bother doing an order in for the textbooks cause new spec ones have mistakes and they get fixed afterwards but no point spending money on books with mistakes and having loads of them