Answer:
The problem in the first statement is that it does not say that the lines must be in the same plane.
Suppose in a 3D coordinate axis two lines as:
z = 0, y = 0 (this is the x-axis)
y = 1, x = 0 (this line is parallel to the z-axis but one unit above).
Those two lines are not parallel, and also never meet, so the definition is wrong.
The actual definition should be:
"Parallel lines are two lines that lie on the same plane and never meet"
B: The undefined terms are point, line, plane,...
An example can be "Plane", because if our lines do not lie on the same plane, then we can not use the concept of "parallel lines".
In mathematics, the word 'of' always means multiplication, so to find out what 15% of $10.00 is, all we need to do is multiply the percentage by the dollar amount we are reducing.
In order to do this, we must first convert the percentage into a decimal. To do this, we can either divide the percentage by 100, or (my personal shortcut) just shift the decimal point over two places to the left.
15% = 0.15
So now, we can multiply.
0.15 * 10 = 1.5
which is our answer.
15% of $10.00 is $1.50.
Hope that helped! =)
