How do you solve #8/12=r/(r+1)#?

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Answer 1 · 2016-09-15T06:49:23

Cross multiply, then solve as usual.

Cross multiply.

#8(r+1)=12r#

Expand the left-hand side.

#8r+8=12r#

Subract #8r# from both sides.

#8=12r-8r#

Simplify.

#8=4r#

Divide both sides by #4#.

#8/4=r#

Simplify.

#2=r#

Switch sides.

#r=2#

Answer 2 · 2016-09-15T06:49:29

#r=2#

#8/12=r/(r+1)#
#=> 2/3=r/(r+1)#

#=>3r=2(r+1)#
#=> 3r=2r+2#
#=> r=2#