Wednesday

September 17, 2014

September 17, 2014

Posted by **Anonymous** on Thursday, February 23, 2012 at 8:54am.

8/(21-y) = 12/(y+19)

I think the answer is y = 5, i just need to know how to do work out. i done some solution like this

first multiply by(21-y)(y+19)(assuming that y = 21 and y = 19:

(21-y)(y+19)8/(21-y) = (21-y)(y+19)12/(y+19)

then cancel and multiply out the brackets:

8(y+19) = 12(21-y)

that is

8x+152 = 12x-96

finally,rearrange the equation as

160x = 104

- math -
**MathMate**, Thursday, February 23, 2012 at 9:56amy=5 is correct.

To multiply by (21-y)(y+19), y must*not*equal 21 nor -19.

Correct until

8(y+19) = 12(21-y)

Expand:

8y+152=-12y+252

20y=100

y=5

**Answer this Question**

**Related Questions**

Math - how do i solve this: a over b divided by 11 over c = d over 6 I have to ...

algebra - Also, I belive that #4 is D. I drew out a graph and it is symmetrical ...

Algebra 2 - Before I go on and give you the problenms let me explain. i am not ...

Algebra 2 - Before I go on and give you the problenms let me explain. i am not ...

maths - for this equation x^2 - x = 0 would x = 1 i think this is the answer but...

Mathematics - Can someone explain to me how to solve complex fractions as if I ...

Algebra - Hi, I have had to factorise the equation x^2 + x - 30 = 0, which I ...

math - i need some to explain how to turn 1.05 into a fraction Do you know how ...

physics - Okay, I have an example problem that I'm trying to solve that comes ...

5th grade math (dividing fractions) - Hi.. I need help figuring out this problem...