## Search found 7 matches

Thu Apr 05, 2012 2:54 am
Forum: Intermediate Algebra
Topic: Exponential decay, growth: radioactive element, petri dish
Replies: 1
Views: 2613

### Exponential decay, growth: radioactive element, petri dish

A radioactive element has a count of 120. Four weeks later, the count is 104. Find the daily rate of decay. Another one I need help with... A petri dish contains a bacteria count of 6000. Two days ago, the count was 9720. What will the count be 5 days from now if the daily rate remains the same?? I ...
Thu Apr 05, 2012 2:52 am
Forum: Intermediate Algebra
Topic: Expoential Growth: One hundred dollars is invested in 90 day
Replies: 5
Views: 4021

### Re: Expoential Growth: One hundred dollars is invested in 90

Thanks, I figured it out.
Sun Apr 01, 2012 5:02 pm
Forum: Beginning Algebra
Topic: Exponents: (3^2x)(9^x), (a^2)^b (a^b)^2, a^-4/b^-4
Replies: 3
Views: 2480

### Re: Exponents: (3^2x)(9^x), (a^2)^b (a^b)^2, a^-4/b^-4

What do you mean try turning everything into power on 3? I'm confused on that one.. The rest still make sense and I'm good on, thanks.
Sat Mar 31, 2012 5:40 pm
Forum: Intermediate Algebra
Topic: Expoential Growth: One hundred dollars is invested in 90 day
Replies: 5
Views: 4021

### Re: Expoential Growth: One hundred dollars is invested in 90

The thing is is that they're teaching me stuff with all those different equations, my teacher taught us y=a*b^x and says we should be able to use that to figure out this problem. I'm SUPER confused. Lol
Sat Mar 31, 2012 5:18 pm
Forum: Intermediate Algebra
Topic: Expoential Growth: One hundred dollars is invested in 90 day
Replies: 5
Views: 4021

### Re: Expoential Growth: One hundred dollars is invested in 90

Yeahh, the value of "b" is the rate change, that's what I'm having trouble figuring out. That's what we are looking for.. Thanks for the link.
Fri Mar 30, 2012 10:42 pm
Forum: Beginning Algebra
Topic: Exponents: (3^2x)(9^x), (a^2)^b (a^b)^2, a^-4/b^-4
Replies: 3
Views: 2480

### Exponents: (3^2x)(9^x), (a^2)^b (a^b)^2, a^-4/b^-4

(3^2x)(9^x)= ?
Does it, or does it not, equal 27^3x

Another...

(a^2)^b (a^b)^2 = a^4b Correct?

Also..

a^-4/b^-4 = (b/a)^-4 That's incorrect, right? Shouldn't it be (b/a)^4 a positive exponent, not a negative?

Thanksssssssss(:
Fri Mar 30, 2012 10:40 pm
Forum: Intermediate Algebra
Topic: Expoential Growth: One hundred dollars is invested in 90 day
Replies: 5
Views: 4021

### Expoential Growth: One hundred dollars is invested in 90 day

One hundred dollars is invested in 90 days. At the end of the term, the investment is worth \$120. Find the growth rate per day. I do NOT get this... My equation was; 120=100 times b^90. Using the formula y= a times b^x Is that equation right, and how do I solve it? Even if it's not right, just PLEAS...