SOLUTION: How would you graph this polynomial 3x² + 4x – 5? Or how do you graph any polynomial. Please Help!!!!!

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Question 188384: How would you graph this polynomial 3x² + 4x – 5? Or how do you graph any polynomial. Please Help!!!!!
Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!


Given: f(x)=3x^2 + 4x -5, wheresystem%28a=3%2Cb=4%2Cc=%28-5%29%29

Find the vertex: x=-b%2F2a=-4%2F%282%2A3%29=-4%2F6=-2%2F3

The x-coordinate of the vertex is -2/3.

To find Y-Intercept, we will calculate f(-2/3).


So the vertex is (-2/3,-19/3)

To find x -intercepts,we solve eqn 3x² + 4x – 5:
Discriminant: b%5E2-4ac=4%5E2-4%2A3%2A-5=16%2B60=76
Then,
x=%28-4%2B-sqrt%2876%29%29%2F%282%2A3%29=%28-4%2B-8.72%29%2F6
x=%28-4%2B8.72%29%2F6=4.72%2F6=red%280.80%29
x=%28-4-8.72%29%2F6=-12.72%2F6=red%28-2.12%29

For y-intercept, let f(x)=0:
y=3%280%29%5E2%2B4%280%29-5=red%28-5%29, Y-intercept
We see the graph:
--->

Thank you,
Jojo