SOLUTION: I have posted this question twice, so if someone could please show some mercy and answer this in a detailed, easy to follow step by step process, I would be so very grateful! Fi

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Question 90550: I have posted this question twice, so if someone could please show some mercy and answer this in a detailed, easy to follow step by step process, I would be so very grateful!
Find the axis of symmetry
y=x^2+7x+5

Found 2 solutions by jim_thompson5910, bucky:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
To find the axis of symmetry, use this formula:

x=-b%2F%282a%29

From the equation y=x%5E2%2B7x%2B5 we can see that a=1 and b=7

x=%28-7%29%2F%282%2A1%29 Plug in b=7 and a=1


x=%28-7%29%2F2 Multiply 2 and 1 to get 2


So the axis of symmetry is x=-7%2F2

Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
The quadratic that you are given is:
.
y+=+x%5E2+%2B+7x+%2B+5
.
Think of setting y = to zero. If you do, the result will be:
.
+x%5E2+%2B+7x+%2B+5+=+0
.
This is now in the standard quadratic form of:
.
ax%5E2+%2B+bx+%2B+c+=+0
.
and you can apply the quadratic formula to solving it. The quadratic formula tells you that
there are two possible answers for x as follows:
.
x+=+-%28b%29%2F%282%2Aa%29+%2B-+%28sqrt%28b%5E2+-+4%2Aa%2Ac%29%29%2F%282%2Aa%29
.
It's a little hard to see until you think about it, but the answers for x are evenly
distributed about -%28b%29%2F%282%2Aa%29. [That's what the + and - signs of the rest of the
answer for x do for you ... they distribute the values of x evenly on both sides of the line
x+=+-%28b%29%2F%282%2Aa%29]. Takes some thought to understand this, but if you can picture it, it
becomes apparent that the vertical line given by x+=+-%28b%29%2F%282%2Aa%29 is the line of
symmetry ... It goes vertically down the middle of the parabola that you get when you
graph an equation of the form y+=+ax%5E2+%2B+bx+%2Bc.
.
Back to your problem. Recall that we arranged it in the standard form of:
.
+x%5E2+%2B+7x+%2B+5+=+0
.
and we said that the standard form was:
.
ax%5E2+%2B+bx+%2B+c+=+0
.
By comparing the form from the problem with the standard form we can see that:
.
a = +1
b = +7
c = +5
.
Now recall from above that we said the line of symmetry was given by the equation:
.
x+=+-%28b%29%2F%282%2Aa%29
.
Just plug in the values for "b" and "a" and you get that the line of symmetry is:
.
x+=+-%287%29%2F%282%2A1%29+=+-7%2F2+
.
This is the equation of a vertical line through the point -7%2F2 on the x-axis.
.
If you graph the original equation of this problem you will get a parabola that drops down
to a low point when x = -7/2 and then rises as x becomes more positive. The axis of
symmetry is the vertical line that goes through that low point on the graph. [In other
problems the axis of symmetry may be the vertical line through the highest point of the
parabola.]
.
Hopefully this will start to make more sense to you as you work more problems of this sort.
Just remember that for a quadratic equation of the form:
.
y+=+ax%5E2+%2B+bx+%2B+c
.
the equation for the line of symmetry is given by x+=+-%28b%29%2F%282%2Aa%29. Hope this helps.