Question

I NEED SERIOUS HELP!! SOMEONE PLEASE EXPLAIN THIS TO ME! The function P(t) = 145e-0.092t models a runner’s pulse, P(t), in beats per minute, t minutes after a race, where 0 ≤ t ≤15. Graph the function using a graphing utility. TRACE along the graph and determine after how many minutes the runner’s pulse will be 70 beats per minute. Round to the nearest tenth of a minute. Verify

Answer 1

Answer:

the runner’s pulse will be 70 beats per minute in 7.9 minutes

Step-by-step explanation:

$P(t) = 145e^{-0.092t}$

Graph the function using a graphing utility.

Graph is attached below.

P(t) is beats per minute

Given P(t) is 70, so we plug in 70 for P(t) and solve for t

$70= 145e^{-0.092t}$

Divide both sides by 145

$\frac{70}{145} =e^{-0.092t}$

Now take ln on both sides

$ln(\frac{70}{145})=ln(e^{-0.092t})$

$ln(\frac{70}{145})=-0.092t$

Divide both sides by -0.092

So t≈7.91564

Round to nearest tenth t= 7.9

We can verify it from second graph