SOLUTION: help me with this question. the directions are slove each equation by graphing. If integral roots cannot be found, estimate the roots by stating the consecutive integers between wh

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Question 416358: help me with this question. the directions are slove each equation by graphing. If integral roots cannot be found, estimate the roots by stating the consecutive integers between which the roots lie. The question is X^2 + 7x + 9.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
I would use the fact that the minimum on the graph is at -b%2F%282a%29
when the form is ax%5E2+%2B+bx+%2B+c, so min = -7%2F2
The roots will be on either side of this. You can try
(1) x+=+-4 andx+=+-3.
Then try
(2) x+=+-5 and x+=+-2,
next
(3) x+=+-6 and x+=+-1
-----------------------
Here's the graph:
+graph%28+400%2C+400%2C+-8%2C+3%2C+-4%2C+10%2C+x%5E2+%2B+7x+%2B+9%29+
You can see that y will change sign when you go
from choice (2) to choice (3) above