Which method, drawing a model or writing an equation

Bob and Joe start from the same point and walk in opposite directions. Bob walks 2 km/h faster than Joe. After 3 hours, they are

valkas [14]

Answer:

Bob = 6km/h, Joe = 4km/h

Step-by-step explanation:

Bob walked 6km/h after 3 hours = 18 km
Joe walked 4km/h after 3 hours = 12 km

Finally, their distance is 30 km.

6 0

2 years ago

johns test grades in his science class are 82, 93, 75, and 89 what is his average? 1. (87.45) 2. (80.00) 3. (90.40) 4. (89.25) 5

inessss [21]

First you add all the numbers together. So you add 82+93+75+89 to get 339. Once you get that, you divide it by the amount of numbers there are. In this case, it's 4. 339 divided by 4 is 84.75.

HOPE THIS HELPS!!

5 0

3 years ago

Read 2 more answers

I NEED HELP PLEASE, THANKS! :)

Alenkasestr [34]

Answer:

Option A

Step-by-step explanation:

This is a great question!

The first thing we want to do here is to graph the system of " inequalities " -

$\begin{bmatrix}2x+9y\le \:100\\ 9x+y\le \:54\end{bmatrix}$

As x is ≥ 0, respectively y ≥ 0, it makes things a lot simpler, as it kind of restricts us to quadrant 1, but not entirely.

First change each inequality to " slope - intercept " form, as such -

$2x + 10y \leq 100,\\10y \leq 100 - 2x,\\y \leq - 1 / 5x + 10\\----------\\9x + y \leq 54,\\y \leq - 9x + 54$

The graphed solutions would be in the attachment. I have colored the region with which the two intersect, and the fact that we are limited to quadrant 1. In this colored region there are 3 major points, ( 5, 9 ), ( 0, 10 ), and ( 6, 0 ). We have to determine which of these are are maximum points, as the minimum are the same. Substitute these values ( ( 5, 9 ), ( 0, 10 ), and ( 6, 0 ) ) into the equation f( x, y ) = 10x + 4y,

$f ( x, y ) = 10( 5 ) + 4( 9 ),\\f ( x, y ) = 86 -\\f ( x, y ) = 10( 0 ) + 4( 10 ),\\f ( x, y ) = 40 -\\f ( x, y ) = 10( 6 ) + 4( 0 ),\\f ( x, y ) = 60$

( 5, 9 ) resulted in the greatest amount, 86. That would make it our maximum point -

<u><em>Solution = Option A</em></u>

3 0

3 years ago

8m + 5n for m= 3 and n=-5

sasho [114]

Answer:

- 1

Step-by-step explanation:

8m + 5n

8(3) + 5(- 5)

24 + (- 25)

24 - 25

- 1

6 0

3 years ago

Read 2 more answers

Round final answers to 3 decimal places.

irina [24]

There are 651.335 million cells in the petri dish after 11 hours and the cells will reach 1 billion cells after 14.068 hours

<h3>How to determine the number of cells after 11 hours?</h3>

The given parameters are:

At t = 0, Bacteria = 140 million

At t = 6, Bacteria = 320 million

This can be represented as:

f(0) = 140

f(6) = 320

An exponential function is represented as:

f(t) = f(0) * r^t

When t = 6, we have:

320 = 140 * r^6

Divide both sides by 140

r^6 = 2.28571428571

Take the 6th root of both sides

r = 1.15

So, we have:

f(t) = f(0) * 1.15^t

Substitute f(0) = 140

f(t) = 140 * 1.15^t

After 11 hours, we have:

f(11) = 140 * 1.15^11

Evaluate

f(11) = 651.33

Hence, there are 651.335 million cells in the petri dish after 11 hours

Time to reach 1 billion cells

This means that

f(t) = 1 billion i.e. 1000 million

So, we have:

1000 = 140 * 1.15^t

Divide by 140

1.15^t = 7.14285714286

Take the logarithm of both sides

t * log(1.15) = log(7.14285714286)

Divide both sides by log(1.15)

t = 14.068

Hence, the cells will reach 1 billion cells after 14.068 hours

Read more about exponential functions at:

brainly.com/question/2456547

#SPJ1

6 0

2 years ago