y-intercept of a log // solve for x of a log

[letsgetaway]

I'm curious if I've got the right idea.

1. Find the y-intercept of y = log₅(1 - x) - 9

Would finding the solution to this problem be like what follows?

*Possible Solution

Calculate log₅(1). Then subtract 9:

. . .log₅(1 - 0) = log₅(1) = 0

. . .log₅(1) - 9 = 0 - 9 = -9

-------------------------------------------------------

2. Solve for x:

. . .log₁₁(x) + log₁₁(x+3) = log₁₁(4)

*Possible Solution

Foil the (x)(x+3) to get x^2+3x. After this, I'm not sure how to approach the log₁₁(4) on the other side of the equation.

 

[galactus]

I'm curious if I've got the right idea.

1. Find the y-intercept of log 5 (1 - x) - 9

Would finding the solution to this problem be like what follows?

*Possible Solution

Calculate log 5 1. Then subtract -9.

log 5 1 = 0
= 0-9
= -9Correct
-------------------------------------------------------

2. Solve for x. Log 11 (x) + Log 11 (x+3) = Log 11 (4)

*Possible Solution

Foil the (x)(x+3) to get x^2+3x. After this, I'm not sure how to approach the log 11 (4) on the other side of the equation.

You've got it. Just set equal to 4.

x(x+3)=4, x=1

 

[letsgetaway]

Thank you!