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anonymous
 one year ago
Solve for x: 3x + 7 = 12
anonymous
 one year ago
Solve for x: 3x + 7 = 12

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Those lines just mean that the x+7 is positive so just think of it as parentheses. Distribute the 3 in (x+7).

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0You should get 3x21.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Now try to solve this.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0It should be easier.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Then the answer would be x=6. But you aren't done there. When I told you that the absolute value is like parentheses, I was trying to not confuse you by saying that now you have to put a negative in front of the parentheses.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Absolute values will always be positive and negative when it comes to equations.

freckles
 one year ago
Best ResponseYou've already chosen the best response.1you should get two answers first divide both sides by 3 x+7=4 you have to solve both equations below: x+7=4 or x+7=4

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So now it should look like this(3){(x+7)}=12

anonymous
 one year ago
Best ResponseYou've already chosen the best response.03(x7)=12 3x+21=12 3x=2112 3x=33 x=11

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Yes that's the second answer.

freckles
 one year ago
Best ResponseYou've already chosen the best response.1x=6 gives a false equation 36+7=12 doesn't hold 313=12 3(13)=12 39=12 see this isn't the same thing on both sides so x=6 isn't a correct solution

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0thxs i got my answers you guys are the best

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I don't think it's suppose to equal back to the problem @freckles. Look at this link. http://www.purplemath.com/modules/solveabs.htm

freckles
 one year ago
Best ResponseYou've already chosen the best response.1yes it is in order for x=c to be a solution it must satisfy the equation

freckles
 one year ago
Best ResponseYou've already chosen the best response.1the first equation was just solved incorrectly

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0When you plug in the 1st x of the equation from the picture. It doesn't equal 7. The second x does though.

freckles
 one year ago
Best ResponseYou've already chosen the best response.13(x+7)=12 3x21=12 add 21 on both sides 3x=12+21 3x=2112 3x=9 divide by 3 on both sides x=3 as you see pluggin x=3 into original this does satisfy initial equation 3x+7=12 replace x with 3 33+7=12 34=12 3(4)=12 12=12 this is a true equation so x=3 is a solution just like x=11 is also a solution since 3x+7=12 pluggin in 11 for x 311+7=12 34=12 3(4)=12 12=12 same thing on both sides the equation is true x=11 is also a solution so the solution set is {3,11}

freckles
 one year ago
Best ResponseYou've already chosen the best response.1@200205650 you have to plug into the original equation

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Okay then never mind. You are right.
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