Answer:
Divide each number by 2 then translate them
<span>X + 1.5 ≤ 5
X ≤ 3.5
"Julia is allows to watch no more than 5 hours of television"
X ≤ 5
"She has watched 1.5 hours"
X + 1.5 ≤ 5
So the inequality to solve is:
X + 1.5 ≤ 5
Now to solve it, just subtract 1.5 from both sides:
X + 1.5 ≤ 5
X + 1.5 - 1.5 ≤ 5 - 1.5
X ≤ 3.5
So Julia can watch up to 3.5 more hours of TV this week.</span>
The total number of articles is 14 and only 7 can be published. Since what is asked is the ways to assemble the 7 articles, this is a permutation problem.
14P7 = <span>17297280 ways
If order is not of concern, the problem is just a combination problem
14C7 = </span><span>3432 ways</span><span />
The equation of a sphere is:
(x – h)^2 + (y – k)^2 + (z – l)^2 = r^2
where h, k and l are the coordinates of the center of the
sphere
Using the midpoint formula, the coordinate of the center
is:
h = (-4 + 6) / 2 = 1
k = (7 + -5) / 2 = 1
l = (6 + 7) / 2 = 6.5
so the equation becomes:
(x – 1)^2 + (y – 1)^2 + (z - 6.5)^2 = r^2
we plug in any point, in this case point P to solve for r:
(-4 -1)^2 + (7 – 1)^2 + (6 - 6.5)^2 = r^2
r^2 = 61.25
So the full equation is:
<span>(x – 1)^2 + (y – 1)^2 + (z - 6.5)^2 = 61.25</span>