2 times 8 equals 16 + 10 equals 26
hmmm, between the three options I would go with the second one since the number of 1-foot cubes equals exactly the volume of the fish tank.
But to truly calculate the volume
5 x 3 = 15
15 x 3 = 45
45 is the volume of the fish tank
The normal vector to the plane <em>x</em> + 3<em>y</em> + <em>z</em> = 5 is <em>n</em> = (1, 3, 1). The line we want is parallel to this normal vector.
Scale this normal vector by any real number <em>t</em> to get the equation of the line through the point (1, 3, 1) and the origin, then translate it by the vector (1, 0, 6) to get the equation of the line we want:
(1, 0, 6) + (1, 3, 1)<em>t</em> = (1 + <em>t</em>, 3<em>t</em>, 6 + <em>t</em>)
This is the vector equation; getting the parametric form is just a matter of delineating
<em>x</em>(<em>t</em>) = 1 + <em>t</em>
<em>y</em>(<em>t</em>) = 3<em>t</em>
<em>z</em>(<em>t</em>) = 6 + <em>t</em>
Its an equilateral triangle so all sides are equal.
2x + 5 = 4x - 1
5 = 2x - 1
6 = 2x
3 = x
Do you get it?
