9, 5, 3
9, 6, 2
8, 7, 2
8, 6, 3
8, 5, 4
This is just a number of combinations. There are a few more.
A) We are told that at 2 hours, the velocity is 18 km/h and at 4 hours, the velocity is 4 km/h. Since we are relating two variables - let's give them names.
Let x = time and y = velocity. Since the velocity depends on the time (that is, the time influences velocity), this is a linear function. Any linear function can be written in slope intercept form as y = mx + b. The problem wants the situation in standard from of Ax + By = C, which can be found from slope intercept form.
So now we can make our line. Consider the ordered pairs of (2,18) and (4, 4) with them in (x, y) form. Finding the slope, m, between these points is as such:
m = y₂-y₁ / x₂-x₁
m = 4 - 18 / 4 - 2
m = -14 / 2 = -7.
Our slope is -7.
We take m = -7, x = 4, and y = 4 (it goes 4 km/h in 4 hrs) and use those three things to find the y-intercept.
y = mx + b
4 = -7 * 4 + b
4 = -28 + b
32 = b
So our equation of the line is y = -7x + 32. To put the equation into standard form, we need to place all the variables on one side of the equals sign, all the numbers on the other.
y = -7x + 32
7x + y = 32
In standard form, the equation for this situation is 7x + y = 32
***
To find out the velocity at 8 hours, we evaluate our function at x = 8. Either equation (standard form or slope intercept) works; we use standard form.
7x + y = 32
7*8 + y = 32
56 + y = 32
y = -24
At a time of eight hours, the bicycle is moving at -24 km/h.
Answer:
600 is 1/10 of 600
Step-by-step explanation:
Multiply 600 by 10 and you get 6000
5. After 6 hours, the concentration is halved. After 12 hours, it will be quartered. If the original concentration is 200 nmol, a quarter is 50 nmol.
14. The population doubles after 3 hours, and a day is 24 hours. That means that the original population should be multiplied by
, or
. 3 million times
is 3 * 256 million, or 768 million.
15. The concentration is halved every 8 hours and the original concentration is 100 nmol. So now, how many times do you halve 100 to get to 12.5?
100/2 = 50, 50/2 = 25, 25/2 = 12.5. That's three times. 3 * 8 is 24 hours, or 1 day.