Answer:
Amount invested at 8% is $9000 and amount invested at 18% is $21000.
Step-by-step explanation:
Let amount invested at 8% be x.
Let amount invested at 18% be y.
We get the 1st equation as:
........(1)
We get the second equation as:

=> 
or getting rid of the decimal by multiplying by 100 on both sides.
........(2)
Multiplying (1) by 8 and subtracting from (2) we get
So, y = 21000
And 

So, x = 9000
Therefore, amount invested at 8% is $9000 and amount invested at 18% is $21000.
Answer:
It would roll in this direction.

Step-by-step explanation:
It would roll to the direction of maximum decrease, which is the -1 times the direction of maximum increase, which is given by the gradient of the function.
Since

For this case, the gradient of your function would be

And -1 times the gradient of your function would be

Then, at

So it would go towards

The magnitud of that vector is

and to conclude it would roll in this direction.

Answer:am working on this to study guide
Step-by-step explanation:
3x^2+12x+15=0
Then divide by 3 to get the x by itself.
x^2+4x+5=0
Factor to (x+5) (x-1) and solve for the two values of x.