How do you solve #\frac { 9y + 8} { 4} = \frac { 3y + 5} { 2} + 7#?

2 Answers
Mar 4, 2017

#y = 10#

Explanation:

#(9y+8)/4 = (3y+5)/2+7" "# Multiply both sides by 4

#9y+8 = 4((3y+5)/2+7)#

#9y+8 = 2(3y+5)+28#

#9y+8 = 6y+10+28#

#9y-6y = 38-8#

#3y = 30#

#y = 30/3#

#y = 10#

hope that helped

:-)

Mar 4, 2017

#y=10#

Explanation:

To eliminate the fractions in the equation, multiply ALL terms on both sides by the #color(blue)"lowest common multiple"# ( LCM ) of 4 and 2, the denominators of the fractions.

The LCM of 4 and 2 is 4

#(cancel(4)^1xx(9y+8)/cancel(4)^1)=(cancel(4)^2xx(3y+5)/cancel(2)^1)+(4xx7)#

#rArr9y+8=2(3y+5)+28#

distribute bracket.

#9y+8=6y+10+28#

#rArr9y+8=6y+38#

subtract 6y from both sides.

#9y-6y+8=cancel(6y)cancel(-6y)+38#

#rArr3y+8=38#

subtract 8 from both sides.

#3ycancel(+8)cancel(-8)=38-8#

#rArr3y=30#

divide both sides by 3

#(cancel(3) y)/cancel(3)=30/3#

#rArry=10#

#color(blue)"As a check"#

Substitute this value into the equation and if the left side equals the right side then it is the solution.

#"left side "=((9xx10)+8)/4=98/4=24.5#

#"right side "=((3xx10)+5)/2+7=35/2+7=24.5#

#rArry=10" is the solution"#