Tutor MathsGuru: Ask me for your burning Maths questions!

[S-H]

Please help me with this questions:-


1) Find the possible equations of the circle which touches both coordinate axes and passes through (2,1).

Thank you.

[syeda]

Hi,

I have a lot of difficulty in teaching Fractions to 4th Grader.
If any one could help me in solving several questions,drop me a message,I
would contact her…

[lazy me]

Hi, pls help me with this p4 question.


David n Junwei had an equal amount of money. After David received twice the amount of money that he had at first and junwei spent $12, David had 5 times as much money as junwei. How much money did junwei have at first?

Tq

[MathIzzzFun]

lazy me:

Hi, pls help me with this p4 question.


David n Junwei had an equal amount of money. After David received twice the amount of money that he had at first and junwei spent $12, David had 5 times as much money as junwei. How much money did junwei have at first?

Tq

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cheers.

[lazy me]

Mathizzzfun, tq so much. U made it so easy ! Really appreciate our reply

[silverhorse]

Need help : Roy bought an equal number of pens and pencils. The pencils are sold at 5 for $3 and pens are sold at 4 for $5. He paid $65 more for pen than pencils. how many pen and pencils did he buy?


Thank you.

[ChewingPencilLine]

silverhorse:

Need help : Roy bought an equal number of pens and pencils. The pencils are sold at 5 for $3 and pens are sold at 4 for $5. He paid $65 more for pen than pencils. how many pen and pencils did he buy?


Thank you.

Lowest common multiple of 5 and 4 = 20

Let's say you buy 20 pens and 20 pencils,
(question says an equal number of pens and pencils)

Total cost of 20 pens = 20 / 4 x $5 = $25
Total cost of 20 pencils = 20 / 5 x $3 = $12

The 20 pens cost $25 - $12 = $13 more than the 20 pencils.

However, the question says that Roy paid $65 more for the pens than the pencils, not $13.

Therefore, $65 / $13 = 5 sets
Final answer is hence as follows:
Roy bought 5 x 20 = 100 pens and 100 pencils.

[ChewingPencilLine]

Herbie:

Hi! Can advise how to solve this modulus function?

A. I2x - 5l + 2l10 -4xl =15

B. lx-3l/lxl=2

A. |2x - 5| + 2 |10 - 4x| = 15
|2x - 5| + 4 |5 - 2x| = 15
|2x - 5| + 4 |-(2x-5)| = 15
|2x - 5| + 4 |2x-5| = 15
5 |2x - 5| = 15
|2x - 5| = 3
therefore, 2x - 5 = -3 or 2x - 5 = 3
solve for x = 1 or x = 4.

B. |x - 3| / |x| = 2
|(x - 3) / x| = 2
therefore, (x - 3) / x = -2 or (x - 3) / x = 2
solve for x = 1 or x = -3

[silverhorse]

ChewingPencilLine:

silverhorse:

Need help : Roy bought an equal number of pens and pencils. The pencils are sold at 5 for $3 and pens are sold at 4 for $5. He paid $65 more for pen than pencils. how many pen and pencils did he buy?


Thank you.

Thanks Chewing Pencil Line. Appreciate it.


Lowest common multiple of 5 and 4 = 20

Let's say you buy 20 pens and 20 pencils,
(question says an equal number of pens and pencils)

Total cost of 20 pens = 20 / 4 x $5 = $25
Total cost of 20 pencils = 20 / 5 x $3 = $12

The 20 pens cost $25 - $12 = $13 more than the 20 pencils.

However, the question says that Roy paid $65 more for the pens than the pencils, not $13.

Therefore, $65 / $13 = 5 sets
Final answer is hence as follows:
Roy bought 5 x 20 = 100 pens and 100 pencils.

[ChewingPencilLine]

No problem. Glad to be of help… As long as it doesn’t take up too much time, LOL.


Which is why I am not going to give a complete answer to the question "Find the possible equations of the circle which touches both coordinate axes and passes through (2,1)."

Basically, there should only be one possible circle right? In the first quadrant. It is not possible for a circle to touch the coordinate axes and pass through (2,1) if located in the other 3 quadrants.

The circle should have a radius of 1 unit (larger of 2, 1 divided by 2) and should be centered at (1,1). I trust you should be able to form the equation of the circle on your own by plugging in the values into your general equation for circles.