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# Maths help watch

1. can you solve this?

The value of x(y-4)/5 is -2
Work out the possible pair of values for x and y

Thank you
2. bump
3. (Original post by student.feed)
can you solve this?

The value of x(y-4)/5 is -2
Work out the possible pair of values for x and y

Thank you
Post the full question.
4. (Original post by Zacken)
Post the full question.
That is all. I have attached the paper. It is question 1. Even my maths teacher, didn't know the answer
Attached Images
5. RevisionEx.pdf (131.4 KB, 477 views)
6. (Original post by student.feed)
That is all. I have attached the paper. It is question 1. Even my maths teacher, didn't know the answer
Do this:

x(y-4) = -10

Now what two numbers multiply to make -10?

For example, -2 and 5 do, x=-2 and y-4 = 5 means x=-2, y=9 works.

Or x=5, y-4 = -2 works.

Or x=10, y-4 = -1 works.

etc...

You really only need to use one of the above pairs.
7. x=2 and y=-1
8. (Original post by student.feed)
can you solve this?

The value of x(y-4)/5 is -2
Work out the possible pair of values for x and y

Thank you
$1. [x(y-4)]\div 5 = -2$

$2. [x(y-4)] = -2\times 5$

$3. [x(y-4)] = -10$

$4. xy- 4x= -10$

$5. y= (-10 + 4x\div x)$

Then the x's cancel out

$6. y= -10 + 4$

$7. y= -6$

So now you know what Y is, you can substitute it into the original equation to get the value of X

$8. x(-6-4)= -10$

$9. -10x = -10$

$10. x= -10\div -10$

$11. x=1$

$Final-Answer:$

x=1
y= -6

BTW, I have no clue if this is right! Correct me if I'm wrong! I was just improvising...
9. (Original post by Zacken)
Do this:

x(y-4) = -10

Now what two numbers multiply to make -10?

For example, -2 and 5 do, x=-2 and y-4 = 5 means x=-2, y=9 works.

Or x=5, y-4 = -2 works.

Or x=10, y-4 = -1 works.

etc...

You really only need to use one of the above pairs.
Thank you very much
10. (Original post by amanii_ox)
BTW, I have no clue if this is right! Correct me if I'm wrong! I was just improvising...
It's wrong.
11. (Original post by amanii_ox)
$1. [x(y-4)]\div 5 = -2$

$2. [x(y-4)] = -2\times 5$

$3. [x(y-4)] = -10$

$4. xy- 4x= -10$

$5. y= (-10 + 4x\div x)$

Then the x's cancel out

$6. y= -10 + 4$

$7. y= -6$

So now you know what Y is, you can substitute it into the original equation to get the value of X

$8. x(-6-4)= -10$

$9. -10x = -10$

$10. x= -10\div -10$

$11. x=1$

$Final-Answer:$

x=1
y= -6

BTW, I have no clue if this is right! Correct me if I'm wrong! I was just improvising...
Thank you
12. (Original post by student.feed)
Thank you very much
No worries. By the way, the question in your document is very much different to the question you asked on here.
13. (Original post by SargentZenj2)
x=2 and y=-1
Thank you
14. (Original post by SargentZenj2)
x=2 and y=-1
Yes that is one of the possible values!!
15. (Original post by Zacken)
No worries. By the way, the question in your document is very much different to the question you asked on here.
Oh. Anyways thank you for letting me know
16. (Original post by student.feed)
Thank you
No problem, BTW there are other ways to work it out, there is a range of possible values, this is just one possible value
17. (Original post by student.feed)
Thank you
FYI this was just plain wrong. Ignore it, just look at Zacken's post.
18. (Original post by IrrationalRoot)
FYI this was just plain wrong. Ignore it, just look at Zacken's post.
Yes, I did
19. SHOULD'VE LOOKED LIKE THIS SOZ!
5. y = (-10+4x)/ x
(Original post by AnIndianGuy)
Well step 5 is incorrect. When you divide through by x 10 should also be divided through by x
20. (Original post by student.feed)
can you solve this?

The value of x(y-4)/5 is -2
Work out the possible pair of values for x and y

Thank you
x(y-4) = -10
y-4 = -10/x
y = (-10/x + 4)
x(-10/x + 4 - 4) = -10
x(-10x) = -10
-10x^2 + 10 = 0
-10(x^2 - 1) = 0
x^2=1
x=1
y = (-10/1 + 4)
y= -6

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