The second answer choice.
75 42
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100 x
75 x= 4200
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75 75
x = 56
Answer:

Step-by-step explanation:
The axis of symmetry can be calculated using the formula:

First we must determine a and b from the quadratic:
. This is in standard form, with the highest power first in descending order.
Standard form is also: 
If we compare this to the quadratic given, we can conclude that:

Substitute the values for a and b into the formula.

Multiply in the denominator.

Divide.

This can also be determined from the graph. It is the x-coordinate of the vertex or the maximum/minimum. It divides the quadratic into 2 symmetrical halves.
Answer:
x
^2/
6
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