Question

can somebody please help me understand what happening in the attached.

Answer 1

article 64

Answer 2

are you asking the explanation of each step?

Answer 3

yes

Answer 4

first, we let \[z=\frac{ x+y }{ x-y }\]
so, we can rewrite the equation as \[2z+\frac{ 10 }{ z }=9\]

Answer 5

now 10((x-y)/(x+y))=10/z

Answer 6

consider that \[z= \frac{ x+y }{ x-y }\]
so, what is \[\frac{1}{z}\] ?

Answer 7

raised to the -1 power

Answer 8

hhmm...,
\[z=\frac{ x+y }{ x-y }\]
so,
\[\frac{ 1 }{ z }=\frac{ 1 }{ \frac{ x+y }{ x-y} }=1\times \frac{ x-y }{ x+y }= \frac{ x-y }{ x+y }\]

therefore,
\[10 \frac{ x-y }{ x+y } =10 \times \frac{1}{z} = \frac{10}{z} \]

Answer 9

so (x-y)/(x+y)=1/z

Answer 10

thanks for clearing that up for me.

Answer 11

you're welcome...,
just ask if you still confused about the rest :)