Carry out the mult.: f(x) = -[x^2 - 21x + 9x - 189]
Combine like terms: f(x) = -[x^2 - 12x - 189]
Eliminate the brackets [ ]: f(x) = -x^2 + 12x + 189
Identify coefficients a, b and c: a= -1, b=12, c=189
The equation of the axis of symmetry is x = -b/(2a), which here equals
x = -(12)/[2(-1)], or x = 6
This is also the x-coordinate of the vertex. Plug x=6 into the original equation to calculate the y-coordinate.
First, for end behavior, the highest power of x is x^3 and it is positive. So towards infinity, the graph will be positive, and towards negative infinity the graph will be negative (because this is a cubic graph)
To find the zeros, you set the equation equal to 0 and solve for x
x^3+2x^2-8x=0
x(x^2+2x-8)=0
x(x+4)(x-2)=0
x=0 x=-4 x=2
So the zeros are at 0, -4, and 2. Therefore, you can plot the points (0,0), (-4,0) and (2,0)
And we can plug values into the original that are between each of the zeros to see which intervals are positive or negative.
Plugging in a -5 gets us -35
-1 gets us 9
1 gets us -5
3 gets us 21
So now you know end behavior, zeroes, and signs of intervals
Hope this helps<span />
We have been given that Tony wants to save $10000 in 6 years.
That means future value S = $10000
Time t= 6 years
Interest rate = 4% yearly = 0.04 yearly
n=12 months per year
Now we have to find monthly payment to recieve $10000 in 6 years. so we need to apply monthly payment formula which is









which is approx $123.
Hence final answer is C) $123.
He is leaving 20% tip of the bill of $58
20% extra
So total amount = 100% + 20% = 120%
120% of 58
(120/100) * 58
1.2 * 58
= 69.6
So total amount Alexi needs to pay = $69.60
19.184*0.46=8.82464 the answer is: 8.82464