Answer:
a) maximum; the parabola opens downward
b) positive; it must lie above the x-axis
c) x = 1.5
Step-by-step explanation:
The x-intercepts of a function are the points where the graph of the function crosses the x-axis. The y-values there are zero.
The "differences" of a function are related to the average slope between adjacent points. Second differences are related to the rate of change of the slope of the function. When <em>second differences are negative</em>, as here, the slope of the quadratic function is decreasing, becoming more negative. We say the <em>curvature</em> of the function is <em>negatve</em>, and that it <em>opens downward</em>.
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<h3>a, b.</h3>
If the graph of the parabola opens downward, and it crosses the x-axis, it must have a <em>maximum</em> that is a <em>positive value of y</em>.
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<h3>c.</h3>
The graph of a parabola is symmetrical about its vertex. That means points on the same horizontal line are the same distance from the line of symmetry, which must go through the vertex. The x-coordinate of the vertex will be the x-coordinate of the midpoint between the two x-intercepts:
x = (-2 +5)/2 = 3/2
The x-coordinate of the vertex is x = 1.5.
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<em>Additional comment</em>
The attachment shows a table with three evenly-spaced points on the curve. The calculations show first differences (d1) and second differences (d2). You can see that the sign of the second diffference is negative, in agreement with the given conditions.
Answer: $3,664.21
Formula: 
- P = principle/original amount = $3000
- r = rate of interest = 4% = 0.04
- t = time period (in years) = 5
- A = the new amount
- e = Euler's number ≈ 2.718...
Substitute in the values:

<u>Approximately $3,664.21</u>
<em>I think this is how you solve it o_O</em>
Answer:
He used about 15 gallons
Step-by-step explanation: if he drove 617.3 miles and he gets 41 miles per gallon, then we can use the formula 41x=617.3 to solve this formula, we would divide 617.3 by 41 to isolate x. 617.3 divided by 41 is equal to 15 and therefore x = 15
Kilo means 1000 so 1 kiometer=1000 meter
so every 1000 meter=1 kilometer
to convert,, just divide meters by 1000 and get km
2950/1000=2.95km
Answer: C
Step-by-step explanation:
To determine if a triangle is equilateral, you need to see if all the sides have the same length.