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

2 Answers
Sep 15, 2016

Answer:

Cross multiply, then solve as usual.

Explanation:

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#

Sep 15, 2016

Answer:

#r=2#

Explanation:

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

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