What is it called when columns filled with pairs of numbers that have the same ratio

1 answer:

4 0

You can call it a constant proportionality table because it is used to find the constant of proportionality and proportional relationships. (I am not really sure)

You might be interested in

Please ..........help me

Ad libitum [116K]

Answer:

First statement: 10 road workers take 5 days to complete a work, working 2 hours a day.

Let us calculate how many days 2 workers will need, if they were to work at the same pace (i.e. each working 2 hours a day). The workforce is now decreased to 2 divided by 10 = 1/5 (i.e. one-fifth).

Therefore proportionately, the time will increase to 5 days divided by 1/5, (i.e. 5 / (1/5) = 25 days.

We now know that 2 workers will need 25 days to finish the work, if they work for 2 hors a day.

Now the question is what will happen if the two people work 5 hours per day, instead of 2 hours per day?

The labor they put in has increased to 5 divided by 2 = 2.5 (i.e. 2 and half times).

Consequently, the time needed to finish the work will decrease to 25 divided by 2.5 (i.e. ( 25 / 2.5 ) = 10. days.

The answer : 10 Days.

6 0

3 years ago

Write the equation of the line that passes through (−3,1) and (2,−1) in slope-intercept form

Alex787 [66]

Answer:

$y=-\frac{2}{5}x-\frac{1}{5}$

Step-by-step explanation:

The equation of a line is y = mx + b

Where:

m is the slope

b is the y-intercept

First, let's find what m is, the slope of the line.

Let's call the first point you gave, (-3,1), point #1, so the x and y numbers given will be called x1 and y1.

Also, let's call the second point you gave, (2,-1), point #2, so the x and y numbers here will be called x2 and y2.

Now, just plug the numbers into the formula for m above, like this:

$m = -\frac{2}{5}$

So, we have the first piece to finding the equation of this line, and we can fill it into y=mx+b like this:

$y=-\frac{2}{5}x + b$

Now, what about b, the y-intercept?

To find b, think about what your (x,y) points mean:

(-3,1). When x of the line is -3, y of the line must be 1.
(2,-1). When x of the line is 2, y of the line must be -1.

Now, look at our line's equation so far: $y=-\frac{2}{5}x + b$ . $b$ is what we want, the - $-\frac{2}{5}$ is already set and x and y are just two 'free variables' sitting there. We can plug anything we want in for x and y here, but we want the equation for the line that specfically passes through the two points (-3,1) and (2,-1).

So, why not plug in for x and y from one of our (x,y) points that we know the line passes through? This will allow us to solve for b for the particular line that passes through the two points you gave!

You can use either (x,y) point you want. The answer will be the same:

(-3,1). y = mx + b or $1=-\frac{2}{5} * -3 + b$ , or solving for b: $b = 1-(-\frac{2}{5})(-3)$ . $b = -\frac{1}{5}$ .
(2,-1). y = mx + b or $-1=-\frac{2}{5} * 2 + b$ , or solving for b: $b = 1-(-\frac{2}{5})(2)$ . $b = -\frac{1}{5}$ .