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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 $$2(16 - 9) = 6 + \dfrac{16}{2}$$ $$2(7) = 6 + 8$$ $$14 = 14$$ Thanks from MarkFL
 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. Thanks from agentredlum
 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
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Quote:
 Originally Posted by the john 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.
I'm not sure what you mean. I know I am very bad at maths if that is what you mean, but I want to learn.

Quote:
 Originally Posted by agentredlum 1) $3x - 5 = 3 + 5x$ Subtract $3x$ from both sides
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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