Question

Solve the equation of 2log (2y + 4) = log 9 + 2log (y -1).
A. 3
B. 5
C. 7
D. 21

Answer 1

@Hero @ParthKohli @iambatman

Answer 2

first write both sides of the equation as a single log
then ignore the logs

Answer 3

that is one way, there may be an easier way

Answer 4

Ok so then its B correct?

Answer 5

@TheSmartOne @AlexandervonHumboldt2

Answer 6

\[2\log(2y+4)=\log9+2\log(y-1)\]

Answer 7

\[2\log(2y+4)-2\log(y-1)=\log9\]

Answer 8

\[\log(2y+4)^2-\log(y-1)^2=\log9\]

Answer 9

\[\log \frac{ (2y+4)^2 }{ (y-1)^2 }=\log9\]

Answer 10

\[\log(\frac{ 2y+4 }{ y-1 })^2=\log9\]

Answer 11

Then,cancel both log

Answer 12

\[(\frac{ 2y+4 }{ y-1 })^2=9\]

Answer 13

\[\frac{ 2y+4 }{ y-1 }=\sqrt{9}\]

Answer 14

\[\frac{ 2y+4 }{ y-1 }=3\]

Answer 15

Multiply both sides by y-1

Answer 16

\[\frac{ 2y+4 }{ y-1 }\times~(y-1)=3\times(y-1)\]

Answer 17

\[2y+4=3(y-1)\]

Answer 18

Expand the right side

Answer 19

\[2y+4=3y-3\]

Answer 20

Then,combine like terms and solve for y...

Answer 21

@brooke_ivy99