While you didn't post the instructions for this problem, I can safely assume that you're supposed to factor 8x^2 - 8x - 30.
First, note that all of these terms can be divided by 2:
8x^2 - 8x - 30 = 2(4x^2 - 4x - 15)
Inside the parentheses is a quadratic equation which can't be reduced further. There are a good number of methods that you could use to solve this quadratic:
graphing, completing the square, factoring, quadratic formula, and so on.
I note that the first and last coefficients are 4 and 15.
Thus, possible roots are:
numerator 1, 3, 5, 15, -1, -3, -5, -15
------------------ = -----------------------------------
denominator 1, 2, 4, -1, -2, -4
For example, one root might be -5/2 (-5 from the numerator and 2 from the denominator).
Let's check whether -5/2 is actually a soluion, using synthetic div:
___________________
-5/2 / 4 -4 -15
-10 7/2
__________________
4 -14 Remainder is NOT zero, so -5/2 is not a root.
Lots of possibilities here.
Thus, I'm going to resort to the good old Quadratic Formula to determine the
factors of 4x^2 -4x - 15:
a=4, b= -4 and c = -15
Then the the roots are:
4 plus or minus sqrt(16-4(4)(-15)
x = ------------------------------------------------
8
4 plus or minus sqrt(256) 4 plus or minus 16
= ------------------------------------- = -------------------------------
8 8
= 20/8 and -12/8, or 5/2 and -3/2
Thus, in factored form the polynomial is 8(x-5/2)(x+3/2)
Answer:
A. 20%
Step-by-step explanation:
Last Doctors visit cost $105.
Health insurance through employer paid $84 and you paid $21.
% of cost paid by you will be the amount paid by you divided by the total cost of the doctors visit multiplied by 100%.
That is $21/$105 x 100%
0.2 x 100%
20%
Therefore 20% of the cost of last doctors visit was paid by you .
Answer:
A. 5/72
Step-by-step explanation:
5 + 4 + 3 = 12 marbles
5/12 - the probability that the student picks a blue marble.
1/6 - the probability that 4 is on the cube
The probability that the student picks a blue marble from the bag, and then rolls a 4
5/12 * 1/6 = 5/72
y - y1 = m(x + x1)
m = (y2 - y1)/(x2 - x1) = (-6 - 2)/(-1 - 5) = -8/(-6) = 4/3
y - 2 = 4/3(x - 5) is a possible answer
y + 6 = 4/3(x + 1) is also a possible answer
