Answer:
57 kilometers a day.
Step-by-step explanation:
I just divided 513 by 9 and got that.
Answer:
c) I think'
Step-by-step explanation:
Answer:

Step-by-step explanation:
Brain correctly use a method of completing the square to solve the equation:

His First Step is to: Take the Constant Term to the Right Hand Side

The Next Step Would be to:
- Divide the Coefficient of x by 2
- Square It
- Add it to both Sides
In this case, the Coefficient of x = 7
- Divided by 2 =

- Squaring It, we have:

It is this number
that is added to both sides in the manner below:

Answer:
a. y = -1/2x - 2
Step-by-step explanation:
The correct answer choice can be determined by finding the slope of the line. The slope is the ratio of rise to run.
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<h3>slope</h3>
The x-intercept is 4 units left of the y-axis. As the line "runs" those 4 units, it "rises" -2 units to intercept the y-axis at -2. The slope of the line is ...
m = rise/run = -2/4 = -1/2
In the slope-intercept form of the equation of a line, the slope is the coefficient of x. This information is sufficient to let us choose the first answer choice.
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<h3>equation</h3>
The slope-intercept equation is ...
y = mx +b . . . . . . . slope m, y-intercept b
We know the slope is -1/2, and the y-intercept is where x=0, at y=-2. Then the equation is ...
y = -1/2x -2 . . . . . matches choice A
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<em>Additional comment</em>
When answering multiple-choice questions, you only need to do enough work to tell which answers are <em>not</em> viable.
When we plot the points, we see that the line has negative slope. (eliminates choice C). The slope is shallow, rather than steep (the x-intercept is farther from the origin than the y-intercept), so the magnitude of the slope is less than 1 and choices B and D are eliminated.
Think of it this way: Lets add numbers in pairs, starting at the very outer 2 numbers (19 and 77) then go in by one and add the second number and the second to last (20 and 76), then (21 and 75) and so on. The sum of all of these pairs are all the same: 96. How many 96s will we have? Well since we're coming from each end toward the middle adding pairs we will have half the distance between 19 and 77, that is (77-19)/2 = 29. So we can actually just take 96*29 = 2784. This is the sum of all numbers between 19 and 77