For this case we have the following equation:

Rewriting we have:

Dividing by 2 to both sides of the equation:

We apply the quadratic formula:

We have to:

Substituting:

Thus, we have two roots:

ANswer:

Divide the number of people by the number of plates per pack:
138 / 12 = 11.5
He need to buy 12 packs of plates to have enough.
First we will find the value of x.
To find the value of x we can add angle Q and angle O and set them equal to 180 and solve for x.
We will be setting them equal to 180 since the opposite angles of an inscribed quadrilateral are supplementary.
angle Q + angle O = 180
6x - 5 + x + 17 = 180
7x +12 = 180
7x = 168
x = 24
Now we can use 24 for x and find the value of angle QRO
angle QRO = 2x + 19
angle QRO = 2(24) + 19
angle QRO = 48 + 19
angle QRO = 67
So the answer choice B is the right answer.
Hope this helps :)<span />
Step-by-step explanation:
i don't see any graphs so i don't know how to help
<span>Standard deviation is the square root of variance. Variance is always a non-negative number, since you can't take the square root of a negative number. So neither can be negative </span>