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April 5th, 2014, 07:19 AM  #1 
Newbie Joined: Feb 2014 Posts: 17 Thanks: 0  Help with equation
Hi, I'm trying to solve these equations . Can someone help with them? No multiplication signs and x is the number. 3x −5 = 3 + 5x 2(x − 9) = 6+ x/2 Thanks. 
April 5th, 2014, 09:50 AM  #2 
Math Team Joined: Jul 2011 From: North America, 42nd parallel Posts: 3,372 Thanks: 233 
1) $ 3x  5 = 3 + 5x $ Subtract $3x$ from both sides $ 5 = 3 + 2x $ Subtract $3$ from both sides $ 8 = 2x $ Divide both sides by $2$ $ 4 = x $ Check work in original $$3(4)  5 = 3 + 5(4)$$ $$12  5 = 3  20$$ $$17 = 17$$ 2) $2(x  9) = 6 + \dfrac{x}{2}$ Use the distributive property on the left hand side $ 2x  18 = 6 + \dfrac{x}{2}$ Multiply everything by 2 so we can clear the fraction $4x  36 = 12 + x $ Subtract $x$ from both sides $3x  36 = 12 $ Add 36 to both sides $3x = 48$ Divide both sides by 3 $x = 16$ Check work $$2(16  9) = 6 + \dfrac{16}{2}$$ $$2(7) = 6 + 8$$ $$14 = 14$$ 
April 6th, 2014, 12:55 AM  #3 
Senior Member Joined: Mar 2014 Posts: 112 Thanks: 8 
If I didn't get the answers x = 4, 16 respectively then I would've failed the SAT mathematics. I'm not talking about you, Rob158; again I'm talking about me. If the intended problem for the second one was 2(x  9) = (6 + x)/2 then x = 14. 
April 6th, 2014, 04:59 PM  #4 
Senior Member Joined: Mar 2014 Posts: 112 Thanks: 8 
Again I'm not smart.

April 13th, 2014, 04:32 AM  #5  
Newbie Joined: Feb 2014 Posts: 17 Thanks: 0  Quote:
Many thanks. I have been practicing.  
April 18th, 2014, 07:06 PM  #6 
Senior Member Joined: Mar 2014 Posts: 112 Thanks: 8 
You're not bad at mathematics.


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