The three vectors
,
, and
each terminate on the plane. We can get two vectors that lie on the plane itself (or rather, point in the same direction as vectors that do lie on the plane) by taking the vector difference of any two of these. For instance,


Then the cross product of these two results is normal to the plane:

Let
be a point on the plane. Then the vector connecting
to a known point on the plane, say (0, 0, 1), is orthogonal to the normal vector above, so that

which reduces to the equation of the plane,

Let
. Then the volume of the region above
and below the plane is

Here is the work hope this helps!
1. 1,5 divided by 2 is 0,75 so on the right side its 0,75
2. We make x/8 = 0,75 | *8
so we get: x = 0,75 * 8
which is the same as x = 6
so the answer is x = 6
It would be $1.76 for 1 lb, then you would times that by 61 and if it equals 10.62, it is proportional. I multiplied it and got $109.28/ 62 lbs so it can not form a proportion.