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math question

-1

32 Days Ago

how do i solve this problem
r+5(r-2)=28
3(r+4)+5(r+2)=102

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Grn Xtrm

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32 Days Ago

This question seemingly has nothing to do with c++. In the future dont post math related questions in the programming forums.
As for your problem, what does the question ask you to do? Do you have to solve for the variable r?

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32 Days Ago

1st) Read post 1, although if you PM, someone that knows a little math, he might help you.

2)

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
Let A = r+5(r-2)=28
Let B = 3(r+4)+5(r+2)=102 
 
 
//Break down A
A = r+5(r-2) = 28
= r + 5r - 10 = 28 //distributive rule
= 6r - 10 = 20 //add like trms
= 6r = 20 + 10  //remember switching numbers to the opposite sides mean change its operatorion from + to minus, * to / and vice-versa
so, 6r = 20 + 10,
6r = 30
r = 30/6 = 15/3 = 5
Let A = r+5(r-2)=28
Let B = 3(r+4)+5(r+2)=102 


//Break down A
A = r+5(r-2) = 28
= r + 5r - 10 = 28 //distributive rule
= 6r - 10 = 20 //add like trms
= 6r = 20 + 10  //remember switching numbers to the opposite sides mean change its operatorion from + to minus, * to / and vice-versa
so, 6r = 20 + 10,
6r = 30
r = 30/6 = 15/3 = 5

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
//Break down of B
Let B = 3(r+4)+5(r+2)=102 
 
B = 3r + 12 + 10r + 20 = 102 //Distributive property
=  3r + 10r + 12 + 20 = 102 // re-arrange like terms
= 13r + 32 = 102 //add like terms
 = 13r = 102 - 32 //bring together like terms
 = 13r = 70
 = r = 70/13
//Break down of B
Let B = 3(r+4)+5(r+2)=102 

B = 3r + 12 + 10r + 20 = 102 //Distributive property
=  3r + 10r + 12 + 20 = 102 // re-arrange like terms
= 13r + 32 = 102 //add like terms
 = 13r = 102 - 32 //bring together like terms
 = 13r = 70
 = r = 70/13

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I give up! 
1) What word becomes shorter if you add a letter to it?
2) What does this equal :  (.5u - .5a)(.5u-.5b)(.5u-.5c) ...
3) What is the 123456789 prime numer?

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long time no c

32 Days Ago

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Originally Posted by firstPerson

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A = r+5(r-2) = 28
= r + 5r - 10 = 28 //distributive rule
= 6r - 10 = 20 //add like trms
A = r+5(r-2) = 28 = r + 5r - 10 = 28 //distributive rule = 6r - 10 = 20 //add like trms

Where'd the 28 go and the 20 come from?

Last edited by Dave Sinkula; 32 Days Ago at 10:20 am.

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32 Days Ago

Also with B: this B = 3r + 12 + 10r + 20 = 102 //Distributive property is completely wrong. I have no idea what you're trying to do here.
Look, if r(B)=70/13=5.38... (according to you) then if you substitute 'r' with 5.38... in the original formula, you should get 102; which you don't.

the answer to B is 10. But I'm not going to show the math here, because the OP needs to learn to do his/her own damn homework.

Last edited by niek_e; 32 Days Ago at 10:50 am.

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firstPerson firstPerson is offline

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31 Days Ago

Lol, I was high when I posted that, sorry.

Help with Code Tags

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I give up! 
1) What word becomes shorter if you add a letter to it?
2) What does this equal :  (.5u - .5a)(.5u-.5b)(.5u-.5c) ...
3) What is the 123456789 prime numer?

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niek_e

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31 Days Ago

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Originally Posted by firstPerson

Lol, I was high when I posted that, sorry.

You shouldn't drink and drive and you should smoke and do math. That's how people come up with stuff like the Large Hadron Collider: very dangerous

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iamthwee

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31 Days Ago

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Originally Posted by firstPerson

1st) Read post 1, although if you PM, someone that knows a little math, he might help you.

2)
Help with Code Tags

C++ Syntax (Toggle Plain Text)
Let A = r+5(r-2)=28
Let B = 3(r+4)+5(r+2)=102 
 
 
//Break down A
A = r+5(r-2) = 28
= r + 5r - 10 = 28 //distributive rule
= 6r - 10 = 20 //add like trms
= 6r = 20 + 10  //remember switching numbers to the opposite sides mean change its operatorion from + to minus, * to / and vice-versa
so, 6r = 20 + 10,
6r = 30
r = 30/6 = 15/3 = 5
Let A = r+5(r-2)=28 Let B = 3(r+4)+5(r+2)=102 //Break down A A = r+5(r-2) = 28 = r + 5r - 10 = 28 //distributive rule = 6r - 10 = 20 //add like trms = 6r = 20 + 10 //remember switching numbers to the opposite sides mean change its operatorion from + to minus, * to / and vice-versa so, 6r = 20 + 10, 6r = 30 r = 30/6 = 15/3 = 5
Help with Code Tags

C++ Syntax (Toggle Plain Text)
//Break down of B
Let B = 3(r+4)+5(r+2)=102 
 
B = 3r + 12 + 10r + 20 = 102 //Distributive property
=  3r + 10r + 12 + 20 = 102 // re-arrange like terms
= 13r + 32 = 102 //add like terms
 = 13r = 102 - 32 //bring together like terms
 = 13r = 70
 = r = 70/13
//Break down of B Let B = 3(r+4)+5(r+2)=102 B = 3r + 12 + 10r + 20 = 102 //Distributive property = 3r + 10r + 12 + 20 = 102 // re-arrange like terms = 13r + 32 = 102 //add like terms = 13r = 102 - 32 //bring together like terms = 13r = 70 = r = 70/13

I thought you purposely gave him a dud answer so he would hand it in. Well done you had me fooled.

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Reprise

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31 Days Ago

niek_e is correct about the second equation having r = 10. I didn't see anyone give a correct answer for the first, so I will: r = 19/3.

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Originally Posted by niek_e

You shouldn't drink and drive and you should smoke and do math. That's how people come up with stuff like the Large Hadron Collider: very dangerous

Ha. I refuse to subscribe to the theory that the LHC could end the world.

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firstPerson firstPerson is offline

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#10

30 Days Ago

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Originally Posted by iamthwee

I thought you purposely gave him a dud answer so he would hand it in. Well done you had me fooled.

Maybe, I don't remember what I was thinking at that time.

Help with Code Tags

(Toggle Plain Text)

I give up! 
1) What word becomes shorter if you add a letter to it?
2) What does this equal :  (.5u - .5a)(.5u-.5b)(.5u-.5c) ...
3) What is the 123456789 prime numer?

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