## anonymous one year ago Which graph best shows the function f(x) = 5(2)−x to represent the rate at which a radioactive substance decays?

1. anonymous

2. anonymous

@campbell_st @CBARREDO1

3. CBARREDO1

B and C don't decay, they increase A and D decay but only A has (0,5) on the graph

4. campbell_st

do some basics let x = 0 what is the value of $f(0) = 5 \times 2^0$ that gives the y-intercept and then since the power is negative... as x gets larger f(x) gets smaller

5. anonymous

A is the answer right i just wanted to make sure

6. anonymous

@CBARREDO1

7. CBARREDO1

What?

8. anonymous

iS A RIGHT

9. campbell_st

A is correct, when x = 0 f(x) = 5 and the cruve is decreasing as x gets larger

10. CBARREDO1

As I said the correct answer is A