+0  
 
0
736
1
avatar

Find x when -1/2(2x-3)+1/3(4-6x)=1/4(7-2x)-3

 Apr 17, 2014
 #1
avatar+128731 
0

Find x when -1/2(2x-3)+1/3(4-6x)=1/4(7-2x)-3

OK...to make things a little easier, let's multiply through by the common denominator of 2, 3 and 4, namely - 12. Doing this will get rid of those pesky fractions !!

So we have

(12)*(-1/2)(2x-3)+(12)*(1/3)(4-6x)=(12)*(1/4)(7-2x)-3     =

-6(2x-3) + 4(4-6x) = 3(7-2x) -3  ......  Now, let's "distribute" the "coefficients" outside each parenthesis "across" the terms inside.....this gives....

-12x + 18 + 16 - 24x = 21 -6x - 3  Now.....combining "like" terms, we have

-36x + 34 = 18 - 6x   ......add  36x to each side

 34 = 18  + 30x  .......subtract 18 from both sides....this gives

16 = 30x

Now dividing by 30 on both sides, we have

x = 16/30  which reduces to 8/15

Now, let's check our answer using this....-6(2x-3) + 4(4-6x) = 3(7-2x) -3   so we have

-6(2(8/15) -3) + 4 (4 -6(8/15)) = 3(7- 2(8/15)) - 3   ???

-96/15 + 18 + 16 - 192/15 = 21 - 48/15 - 3 ???

-288/15 + 34 = 18 - 48/15   ???

16 = 240/15  ???

16 = 16  .......√ √ √

And we're finished !!!

 Apr 17, 2014

3 Online Users

avatar