Use technology to find points and then graph the function
y = − log2(x+7) + 5, following the instructions below.
done plotting points
Plot at least five points that fit on the axes below. Click a point to
delete it.
y
9
∞0
7
6
5
4
3 a
2
1
-10-9-8-7-6-5-4-3-2-1 123456789
-1
1 2 3 4 5 6 7 8 9 10
-2
-3
-4
-5
-6
-7
-8
-9
-10
x



Answer :

To find points for the graph of the function y = -log2(x+7) + 5, we will need to select appropriate values for x and calculate the corresponding y values. Here are the steps to follow:

1. Choose values for x.
2. Calculate y using the given function by substituting the chosen x values.
3. Plot the calculated (x, y) points on the graph.
4. Connect the points in a smooth curve.

Let's do this manually using the function y = -log2(x+7) + 5:

Step 1: Choose values for x

It's important to note that the input to the logarithm function must be greater than zero because the logarithm is not defined for zero or negative inputs. Since our function is log2(x+7), we need to ensure that x + 7 > 0, so x > -7.

Let's choose five values for x where x > -7: x = -6.99, -5, -3, -1, 0. (These values are close to -7 but still within the domain of the logarithmic function.)

Step 2: Calculate y for each selected x

For x = -6.99: y = -log2(-6.99 + 7) + 5 = -log2(0.01) + 5 ≈ -(-6.644) + 5 ≈ 11.644
For x = -5: y = -log2(-5 + 7) + 5 = -log2(2) + 5 = -(1) + 5 = 4
For x = -3: y = -log2(-3 + 7) + 5 = -log2(4) + 5 = -2 + 5 = 3
For x = -1: y = -log2(-1 + 7) + 5 = -log2(6) + 5 ≈ -2.585 + 5 ≈ 2.415
For x = 0: y = -log2(0 + 7) + 5 = -log2(7) + 5 ≈ -2.807 + 5 ≈ 2.193

Step 3 & 4: Plot the (x, y) points on the graph and connect them

Now, we can plot the points:

(-6.99, 11.644)
(-5, 4)
(-3, 3)
(-1, 2.415)
(0, 2.193)

On the provided axes, plot these points and connect them with a smooth curve to represent the function. The graph should have a decreasing trend because the function includes a negative log function, which flips the graph of a usual log function upside-down.

Since we cannot show the actual graph here, make sure you operate carefully with a graphing calculator or software to mark the points accurately and then draw your curve through them. If you're using technology for plotting these points, ensure you're within the range where the function is defined and the axes allow for visibility of all points.

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