graph y=-x2-8x-17

In google type:

functions graphs online

When you see list of results click on:

rechneronline.de/function-graphs/

When page be open in blue recatacangle type:

-x^2-8x-17

In Display properties set:

Range x-axis from -8 to 2
Range y-axis from -8 to 2

Then click option Draw

You will see graph of your function.

Your function have y-intercept

y= -17

For x=0

y= -x^2-8x-17= -0^2-8*0-17=0-0-17= -17

If you want to see graph with y-intercept in Display properties set:

Range x-axis from -8 to 2
Range y-axis from -18 to 2

To graph the equation y = -x^2 - 8x - 17, you can follow these steps:

Step 1: Determine the vertex of the parabola.
The vertex of a parabola in the form y = ax^2 + bx + c can be found using the formula x = -b/2a. In this case, a = -1 and b = -8.
x = -(-8) / (2 * -1)
x = 8 / -2
x = -4

To find the corresponding y-coordinate of the vertex, substitute the x-value back into the equation:
y = -(-4)^2 - 8(-4) - 17
y = -16 + 32 - 17
y = -1

So, the vertex of the parabola is (-4, -1).

Step 2: Find the y-intercept.
To find the y-intercept, substitute x = 0 into the equation. In this case, we have:
y = -(0)^2 - 8(0) - 17
y = -17

Therefore, the y-intercept is at (0, -17).

Step 3: Determine the x-intercepts.
To find the x-intercepts, set y = 0 and solve for x.
0 = -x^2 - 8x - 17

This quadratic equation can be solved by factoring, completing the square, or using the quadratic formula. Let's use the quadratic formula here:

x = (-b ± sqrt(b^2 - 4ac)) / (2a)

In this case, a = -1, b = -8, and c = -17.
x = (-(-8) ± sqrt((-8)^2 - 4(-1)(-17))) / (2 * -1)
x = (8 ± sqrt(64 - 68)) / -2
x = (8 ± sqrt(-4)) / -2
x = (8 ± 2i) / -2
x = 4 ± i

Since the discriminant is negative, the equation has no real solutions. However, it does have complex solutions. The imaginary unit "i" represents the square root of -1.

Step 4: Plot the points on a graph.
Based on the calculations from the previous steps, you can plot the vertex at (-4, -1), the y-intercept at (0, -17), and the complex x-intercepts at (4 + i) and (4 - i).

Step 5: Draw the parabolic curve.
Using the plotted points, you can sketch a smooth curve through them, following the shape of a downward-opening parabola.

The final graph of y = -x^2 - 8x - 17 will resemble a symmetric "U" shape, concave downwards, with the vertex at (-4, -1). The curve will intersect the y-axis at (0, -17). The x-intercepts will be complex numbers, (4 + i) and (4 - i), which means they do not fall on the real x-axis but in the imaginary plane.