SOLUTION: graph {{{y=-3x^2-6x-5}}}

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Question 252951: graph y=-3x%5E2-6x-5
Found 2 solutions by drk, oberobic:
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
This is a quadratic opening down with vertex at(-1,-2)
graph%28300%2C200%2C-5%2C+5%2C+-5%2C5%2C-3x%5E2-6x-5%29

Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
With a quadratic equation, your graph will have a single curve in it.
Given the equation:
y=-3x%5E2-6x-5
.
First, you will need to factor it. The factors of 5 are 1 and 5. However, the coefficent of the x-squared term is minus 3. So we can try the quadratic formula, which reveals there is no solution involving only real numbers.
.
Looking at the graph of y=-3x%5E2-6x-5 we can see it is a parabola opening downwards. It never touces the x-axis.
.
graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C-3x%5E2-6x-5%29
.
However, if the equation were:
y+=+-3x%5E2+-16x+-+5
we could factor it as
y+=+%28-3x+-1%29%28x+%2B+5%29
.
This factoring reveals there are solutions: x=-5 and x=-1/3.
Graphing this alternate equation we can inspect it to see the solution:
graph%28500%2C500%2C-10%2C10%2C-10%2C20%2C-3x%5E2-16x-5%29