Answer:
A.
Step-by-step explanation:
We are given the two points (2,7) and (4,-1). In order to determine the linear equation, we need to find the slope and the y-intercept. First, find the slope <em>m.</em> Let (2,7) be x1 and y1, and let (4,-1) be x2 and y2:

Thus, the slope is -4.
Now, to find the y-intercept, we can use the point-slope form. Recall that the point slope form is:

Where (x1, y1) is a coordinate pair and m is the slope.
Use either of the two coordinate pair. I'm going to use (2,7). Substitute them for x1 and y1, respectively:

This is also slope-intercept form. The answer is A.
Answer:
4
Step-by-step explanation:
If x is the third number, then x−1 and x−2 are the second and first numbers.
10(x−2) + 10(x−1) = 10 + 10x
x − 2 + x − 1 = 1 + x
2x − 3 = 1 + x
x = 4
If only + numbers are acceptable, then the numbers divisible by 810 are represented by {810n}, where n = {0, 1, 2, 3, ... }
Answer:
$.56
Step-by-step explanation:
To find the cost of one pen, take the total cost and divide by the number of pens
$1.68/ 3
$.56 per pen
5.6x10^-3 yd/year in feet per day.
There are 3 feet in a yard
(5.6x10^-3)x3=1.68x10^-2 feet/year
Let's take there to be 365 days in the year (Fun fact: The actual duration of our year is <span>365 days 5 hours, 48 minutes 46 seconds)
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Therefore the correct answer is D.</span>