4.) Quadrilateral ABCD has coordinates A ( 0,0), B( 6a, 3b), C ( 3a, 4b), D (a, 3b).
(a) Using coordinate geometry, show that.
(1) AB II CD
(2) AD is not parallel to BC

the direct variation says that:

then the equation is of the form is given by:

            where k is the constant variation.

from the given table:

consider any value of x and m(x)=y

x = 2 and m(x)=y = 3

substitute these value in [1]; we have;

divide both sides by 2 we get;

⇒

check:

put x = -1 and m(x) = -1.5

substitute in the equation:

-1.5 = -1.5                   true

therefore, the function m(x) represents a direct variation

graph of this function as shown below:

30005

yes ok