How do you solve for #x# in # \frac { 9} { w + 8} = \frac { x } { ( w - 7) ( w + 8) }#?

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Answer 1 · 2017-11-15T06:05:15

#=>x = 9w -63#

#\frac { 9} { w + 8} = \frac { x } { ( w - 7) ( w + 8) }#

By transposition:

#=> 9 = \frac { x( w + 8) } { ( w - 7) ( w + 8) }#

#=> 9 = \frac { xcancel( (w + 8)) } { ( w - 7) cancel( w + 8) }#

#=> 9 = \frac { x} { ( w - 7) }#

#=>9(w-7) = x#

#=>9w -63 =x#

#=> x = 9w-63#

Answer 2 · 2017-11-15T06:10:34

#x=9(w-7)#

Start by cancelling #w+8# from both sides of the equation

#9/(cancel(w+8))=x/((w-7)cancel((w+8)))#

#9=x/(w-7)#

Multiply both sides by #w-7#, cancelling it on the right.

#9color(red)((w-7))=x/cancel(w-7)cancel(color(red)((w-7)))#

#9(w-7)=x#

Rewriting from left to right,

#x=9(w-7)#