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.
OK. I used my calculator to evaluate sec(85 degrees).
My calculator doesn't have a "sec" button on it.
But I remembered that
sec of an angle = 1 / (cosine of the same angle) .
So I used my calculator to find cos(85), and then I hit the
" 1/x " key, and got 11.474, which I knew to be sec(85).
Answer:
13! or 6227020800
Step-by-step explanation:
With no restrictions, we can figure out the answer to be 13! by the following analysis:
For the first position in line, there are 13 different students who could fill that spot. If we fill it and proceed to the next position in line, there are now only 12 students left who can fill it, since one is already in line. Then the next position only has 11 possibilities, and the next 10, and so on.
Multiplying all of this together gives us 13*12*11*10*9*8*7*6*5*4*3*2*1 or 13!
I don’t understand the equation but you can use Photomath to solve any equation you need to solve. It’s and app for free.