Because it is an isosceles triangle, the two longer sides are the same length. Therefore multiply 6.3 times 2.
To find the length of the base subtract 12.6 from 15.7 to get 3.1 cm.
No, the graphs of the lines are not parallel because if you simplify 27x-3y=-81, you get y=9x+27, and in order to have the lines parallel, both equations must have the same "m" in y=mx+b. 6 and 9 do not equal, so no they are not parallel.
For example, three points are always coplanar, and if the points are distinct and non-collinear, the plane they determine is unique. However, a set of four or more distinct points will, in general, not lie in a single plane. Two lines in three-dimensional space are coplanar if there is a plane that includes them both.
A. (10/3) / (5/3)
I got it right :)