Answer:
First and second box had 80 and 75 lb flour originally.
Step-by-step explanation:
Let the two boxes contained x lb and y lb of the flour respectively.
Both the boxes contained 155 lb of flour in total.
So the first equation will be,
x + y = 155 --------(1)
If the 20 lb of the flour is taken out then amount of flour in first box = (x - 20) lb
and added to the second box then flour in second box = (y + 20) lb
After the mixing of flour statement says that "the first box will contain
of the flour now in the second box."
For this statement equation will be

19(x - 20) = 12(y + 20)
19x - 12y = 380 + 240
19x - 12y = 620 ------(2)
Equation (1) × 12 + equation (2)
12(x + y) + (19x - 12y) = 155×12 + 620
31x = 1860 + 620
31x = 2480
x = 
x = 80 lb
from equation (1)
80 + y = 155
y = 155 - 80
y = 75 lb.
Therefore, first and second boxes had 80 lb and 75 lb of flour originally.
Answer: No
Step-by-step explanation: First, we need to understand that parallel lines are coplanar lines that do not intersect. On the other hand, perpendicular lines are lines that intersect at a right angle.
However, lines can't be both parallel and perpendicular because they either intersect each other at a right angle or never intersect.
So no, two lines can't be both parallel and perpendicular.
The slope is the change in Y over the change inX: Using the two points given: (3,9) and (1,3)
The slope is (9-3) / (3-1)
Slope = 6 / 2
Slope = 3
The answer is A.