x and y are the packs of organic and inorganic fertilizer, respectively.
pounds of nitrogen added = 2x + 6y = 120
pounds of potassium added = 3x + 2y = 54
eliminate the y terms. subtract the first equation from 3 times the second equation.
9x + 6y = 162
-2x - 6y = -120
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7x = 42
x = 6
y = 18
The velocity, slope, of a line is always (y2-y1)/(x2-x1), in this case:
slope=(8-2)/(7-9)=6/-2=-3
m=-3
If the equation is -3x^2+6x-4 then the vertex is (1,-1)
