3y+4= y/2+9

how do i do this?! im confused :(

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- Aug 10th 2009, 08:43 PMbrainfreezelinear equation problem (again)
3y+4= y/2+9

how do i do this?! im confused :( - Aug 10th 2009, 08:49 PMHallsofIvy
Get the "unknown" (in this case y) by itself on one side of the equation. Here, you might start by getting both "y"s on the left and anything not involving "y" on the right. Since there is a "y/2" added on the left, do the opposite: subtract y/2 from both sides: 3y+ 4- y/2= y/2+ 9- y/2 becomes (3- 1/2)y+ 4= 9 or (6/2- 1/2)y+ 4= (5/2)y+ 4= 9. Now subtract 4 from both sides: (5/2)y+ 4- 4= 9- 4 or (5/2)y= 5. Since y is now

**multiplied**by 5/2, do the opposite: divide both sides by 5/2 (or, same thing, multiply both sides by 2/5): (2/5)(5/2)y= (2/5)(5) or y= 2. - Aug 10th 2009, 09:32 PMbrainfreeze
thanks, but im stuck again lol,

3/4t= -1 7/8

ive tried to move 7/8 to the other side,

but only to fail.

this is what keeps happening

3/4t= -1 7/8

(3/4÷7/8)t = -1

my answer keeps coming up t=-1 1/6

but the answer is -2 1/6

now i know ive done something wrong

but im not sure what it is lol - Aug 10th 2009, 11:34 PMSENTINEL4
$\displaystyle \frac{3}{4}t=-\frac{7}{8}$ Is this the problem you want to solve?

- Aug 11th 2009, 02:57 AMbrainfreeze
thats exactly what im trying to solve

- Aug 11th 2009, 04:00 AMmr fantastic