Answer:
The relation is <u>not</u> a function.
Step-by-step explanation:
A function is a relation in which no two ordered pairs have the same input and different outputs. Whenever you're trying to determine whether a given relation is a function, observe whether each input corresponds with <u><em>exactly</em></u> one output.
In this case, the answer is no. The input value of 10 corresponds with two output values, 4 and 20. It only takes one input value to associate with more than one output value to be <u>invalid</u> as a function.
Therefore, the given relation is <em><u>not</u></em> a function.
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.
She should write it as 4,980 on her report.
Because the two angles add up to equal 90, you would make an equation set to equal 90. On the other end you add the measures of your angles together because they are adding up to equal 90. This would look like 2x+5+35=90 and you solve from here. Add like terms making it 2x+40=90 then you subtract 40 from both sides making it 2x=50 and then divide by 2 on both sides which leaves you with x=25.