Step-by-step explanation:
Recall that for a quadratic equation y = ax² + bx + c in the X-Y plane, the x-location of the vertex (i.e maximum or minimum point) is given by
x @vertex = -b/2a
in this case your quadratic equation is
h = 4 + 20t - 5t² (rearranging in the form y = ax² + bx + c )
h = - 5t² + 20t + 4
hence a= -5, b = 20 and c = 4
applying the formula for vertex
t @ vertex = -b /2a = -(20) / (2)(-5) = -20/-10 = 2
therefore t = 2
Answer:
-6. -8 0 3.4 6 8 14
Step-by-step explanation:
I think I am correct
Answer:
2g :)
Step-by-step explanation:
Answer:
- 33 1/3 liters of 30%
- 16 2/3 liters of 45%
Step-by-step explanation:
Let x represent the liters of 45% solution needed. Then the amount of HCl in the mix is ...
0.45x +0.30(50 -x) = 0.35(50)
0.15x = 0.05(50) . . . . . simplify, subtract 0.30(50)
x = (0.05/0.15)(50) = 50/3 = 16 2/3 . . . liters of 45% HCl
33 1/3 liters of 30% and 16 2/3 liters of 45% HCl are needed.
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<em>Comment on the solution</em>
You may notice that the general solution to a mixture problem of this sort is that the fraction of the mix that is the highest contributor is ...
(mix % - low %) / (high % - low %) = (.35 -.30) / (.45 -.30) = .05/.15 = 1/3