This equation is in vertex form so finding the vertex is easy.
Vertex: (-1,4)
Once you find the vertex, axis of symmetry is easy.
x=-1
Then find y intercept by finding h(0).
h(0)=(0+1)^2-4=-3
Now find x intercepts by solving for x when h(x)=0.
(x+1)^2-4=0
(x+1)^2=4
x+1=±2
x=±2-1
x=1,-3
<span>204
First, lookup a standard normal table and see what the z-score is for 0.025 (one half of 100% - 95%) to allow for equal sized tails. You should find that the z-score is 1.96. That means that 95% of the time, the value should be within 1.96 standard deviations of the mean. Now let's calculate the standard deviation.
800 is 800 - 1200 = -400 to the left of the mean of 1200.
1600 is 1600 - 1200 = 400 to the right of the mean of 1200.
So we are an equal distance of 400 on both sides of the mean. And we know from the z-score of 1.96, that we're 1.96 standard deviations from the mean. So a little division will give us the standard deviation. Which is:
400 / 1.96 = 204.0816327
So the standard deviation of the light bulbs is 204</span>
3x-6=9x
3x-9x=6
-6x=6
X=-1
6x+30=3x
6x-3x=-30
3x=-30
X=-10
