# Solving for y

#### learningmathagain

##### New member
When x=2 and y=3, (xy+3)1/4((x+y)1/2−(y−1)x−1) = ?

The answers are given as multiple choice and I can't seem to get the right one. Here's my expanded equation:

(2*3+3)1/4((2+3)1/2 - (2-1)(3-1) = ?

91/4 (51/2 - 2/2) = ?

91/4 (51/2 - 1) = ?

91/4 (51/2) - 91/4 = ?

And here's where I get stuck. I'm not sure how to simplify this more, but apparently the answer is 151/2 - 31/2 but I'm not sure how that is. Would be happy for some help!

#### R.M.

##### Junior Member
91/4 = (91/2)1/2 = (32x1/2)1/2 = 31/2
See what you can do with this.

#### pka

##### Elite Member
You should give all the choices so that we can see what is going on.
I see one mistake in the first line:
if $$x=2~\&~y=3$$ then $$(y-1)x^{-1}=(2)(2)^{-1}=1$$

#### Jomo

##### Elite Member
(2-1)(3-1)
Although that 3 should be a 2 I am still interested in how you got 2/2. Please show those steps.

#### Jomo

##### Elite Member
91/4 = (91/2)1/2 = ....

#### Subhotosh Khan

##### Super Moderator
Staff member
When x=2 and y=3, (xy+3)1/4((x+y)1/2−(y−1)x−1) = ?

The answers are given as multiple choice and I can't seem to get the right one. Here's my expanded equation:

(2*3+3)1/4((2+3)1/2 - (2-1)(3-1) = ?

91/4 (51/2 - 2/2) = ?

91/4 (51/2 - 1) = ?

91/4 (51/2) - 91/4 = ?

And here's where I get stuck. I'm not sure how to simplify this more, but apparently the answer is 151/2 - 31/2 but I'm not sure how that is. Would be happy for some help!
(2*3+3)1/4((2+3)1/2 - (3-1)(2-1) = ?

91/4 (51/2 - 2/2) = ?

91/4 (51/2 - 1) = ?

91/4 (51/2) - 91/4 = ? ..................... You are almost there...

31/2 (51/2) - 31/2

= (3*5)1/2 - 31/2 .......continue.....

#### learningmathagain

##### New member
91/4 = (91/2)1/2 = (32x1/2)1/2 = 31/2
See what you can do with this.

Thank you! That made everything more clear, I didn't think to simplify this further.