The sum of a and b will be the coefficient of the x term of the trinomial. This can be seen below.
(x + a)(x + b)
= x² + bx + ax + ab
= x² + (a+b)x + ab
x is being multiplied by both a and b individually and the products are being added, so sum of a and b appears as the coefficient of x term.
Thus the answer to this question is option C
The second line of eauation y=-2x+5 is parallel to a since both have the same slope which is -
-2
the first line of equation y=2x-1 is neither perpendicular nor parallel to a since the (slope of this line) x (the slope of a) = 2 x -2 = -4 not -1, so they aren't perpendicular and its slope isn't equal to that of a, so they aren't parallel
the last line of equation y=1/2x+7 is perpendicular to a since (the slope of a) x (the slope of this line) = -2 x 1/2 = -1
<h3>
Answer: 10,080</h3>
Explanation:
There are 8 letters so there are 8! = 8*7*6*5*4*3*2*1 = 40,320 permutations of those letters. However, the letters "O" and "L" show up twice each, so we must divide by 2! = 2*1 = 2 for each instance this happens.
So,
(8!)/(2!*2!) = (40,320)/(2*2) = (40,320)/4 = 10,080
is the number of ways to arrange the letters of "football".
The reason we divide by 2 for each instance of a duplicate letter is because we can't tell the difference between the two "O"s or the two "L"s. If there was a way to distinguish between them, then we wouldnt have to divide by 2.
