Answer:
Step-by-step explanation:
first, we find the slope
slope = (y2 - y1) / (x2 - x1)
(-3,7)....x1 = -3 and y1 = 7
(9,-1)...x2 = 9 and y2 = -1
now we sub
slope(m) = (-1 - 7) / (9 - (-3) = -8 / (9 + 3) = -8 / 12 reduces to - 2/3
y = mx + b
slope(m) = -2/3
use either of ur points...I will use (-3,7)...x = -3 and y = 7
now we sub and find b, the y intercept
7 = -2/3(-3) + b
7 = 2 + b
7 - 2 = b
5 = b
so ur equation is : y = -2/3x + 5 <===
There are 14 floors in the building, because since Juan went up 4 floors, down 3 floors, and up one floor; so we know that he is 2 floors above from where he originally started. Once he went down 9 floors he passed the starting point and went to the bottom of the building. So, the middle must have been the 7th floor. Once I knew that I multiplied 7*2 and it got me 14. So in total there are 14 floors. I hope this helped ^^
Answer: Choice B) 
We have some value m and we're squaring it to get 
To undo this and isolate m, we apply the square root to both sides

There are two solutions here. This is similar to how there are two solutions in something like
(those two solutions being x = 5 and x = -5). Squaring any negative number leads to a positive result because
negative times negative = positive.
I think the answer is A and C!