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:
7a-7
Step-by-step explanation:
2a+2−3a−5+a−4+7a.
Combine like terms
2a-3a+a+7a+2-5-4
7a-7
The answer is C hope this helped you out
Answer:
5 times as many should be your answer.
The height of the tree is the sum of the part below the line parallel to the horizontal and the part above the line parallel to the horizontal.
Height of the part below the line parallel to the horizontal = 18 sin16° = 4.96 meters
Horizontal distance of the tip of the of the shadow from the tree = 18 cos16° = 17.30 meters
Height of the part above the line parallel to the horizontal = 17.3 tan68° = 42.83 meters
Height of the tree = 4.96 + 42.83 = 47.79 meters