SOLUTION: Solve for x: 2^(x+1)+5=17. express the answer to the nearest hundredth. please answer as soon as possible, i do not understand it

Algebra ->  Exponential-and-logarithmic-functions -> SOLUTION: Solve for x: 2^(x+1)+5=17. express the answer to the nearest hundredth. please answer as soon as possible, i do not understand it       Log On


   

Question 443363: Solve for x: 2^(x+1)+5=17. express the answer to the nearest hundredth. please answer as soon as possible, i do not understand it
Answer by swincher4391(1107) About Me  (Show Source):
You can put this solution on YOUR website!
2%5E%28x%2B1%29+%2B+5+=17
Subtract 5.
2%5E%28x%2B1%29+=+12
Take the log(base2) of both sides.
log%282%2C2%5E%28x%2B1%29%29+=+log%282%2C12%29
x%2B1+=+log%282%2C12%29
+x+=+log%282%2C12%29+-1
Use the change of base formula.
log%28b%2Ca%29+=+log%28a%29%2Flog%28b%29
Stupid way to remember this: The base goes in the basement. :P
+x+=+%28log%2812%29%2Flog%282%29%29+-+1
Put this in your calculator to get:
highlight%28x+=+2.58%29