Question

!ANSWER ASAP! Explain how to solve 2x + 1 = 9 using the change of base formula log base b of y equals log y over log b. Include the solution for x in your answer. Round your answer to the nearest thousandth.

Answer 1

Answer:

x=4

Step-by-step explanation:

Well you would try to get x by itself

2x + 1 = 9

2x=9-1

remeber to switch the sings when you transfer them to the other side of the equal sign

2x=8

2x/2=8/2

x=4

Answer 2

Answer:  x = 3

Step-by-step explanation:

Subtract 1

 2^x = 8

Take the log.

 x·log(2) = log(8)

Divide by the coefficient of x.

 x = log(8)/log(2) = log₂(8)

We know that 8 = 2³, so log₂(8) = 3.

 x = 3

_____

If your equation is ...

 2^(x+1) = 9

then

 x + 1 = log(9)/log(2)

 x = log(9)/log(2) -1 . . . . . . change of base formula can be used, but isn't helpful unless you have a calculator that computes log₂(9).

 x ≈ 2.170