Answer:
C
Step-by-step explanation:
Easy peasy
the midpoint between

and

is

just average them
so given that (3,5) is the midpoint of (-4,5) and (x,y)

so by logic

and

times both sides by 2 for everybody
-4+x=6 and 5+y=10
add 4 to both sides for left one and minus 5 from both sides for right
x=10 and y=5
the coordinate of point C is (10,5)
the x coordinate is 10
1. A
Since parallel lines never cross, then there can be no intersection; that is, for a system of equations that graphs as parallel lines, there can be no solution. This is called an "inconsistent" system of equations, and it has no solution.
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2. C
That's right. If a system of equations has a solution, then their graphs intersect, and the point where they intersect is the solution because it's the point that satisfies each equation in the system.
Straight-line graphs with the same slope are parallel lines, and they never intersect, which is another way of saying they have no solution.
C, because the independent variable would be the variable that is changing -- in this case, the temperature. The dependent variable changes according to the independent variable, and is called so because it depends on the temperature of the pool.
Add together your portions 1 + 3 + 5 = 9
divide 72 by 9 = 8
Each portion is multiplied by 8
1 x 8 = 8
3 x 8 = 24
5 x 8 = 40
Your portions are 8kg:24kg:40kg
Is this correct? Add 8 + 24 + 40. Do they equal 72? yes. Your portions are correct.