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:
and the graph would fall at a slower rate to the right
Step-by-step explanation:
we have

Observing the graph
The initial value Ao of the truck is equal to the y-coordinate of the y-intercept of the graph
so
If the depreciation rate was 15% per year, the new formula would be


----> the graph would fall at a slower rate to the right
using a graphing tool
compare the graphs
The best thing I can say is use a online scientific calculator.
Answer: 18 cats
Step-by-step explanation: If the ratio of dogs is 4 and there are 24 dogs then you divided 24 by 4. 24/4 is 6. Then you multiply 3 (the ratio of cats) by 6 which equals 18.
Substituting for values of j:-
S5 = 2(1) + 2(2) + 2(3) + 2(4) + 2(5) = 2+4+6+8+10 = 30 answer