Question

If the point (8. 6) is the result of the composition T3,30 RO,-180º, what are the coordinates of the point prior to the

composition?
A. (-11, -9)
B. (-8, -3)
C. (-8,6)
D. (-5, -3)

Answer 1

The correct answer is A.
`(-11, -9)`.

Explanation:

Given that the point is (8,6)

Let this point be A(8,6).

The composition is T3,30 RO,-180º

First translate the point by 3,3.

Let this point becomes A'.

A' is formed by translation of point A by 3,3

i.e.

x coordinate of A' = x coordinate of A + 3 and

y coordinate of A' = y coordinate of A + 3

So, A' (8+3, 6+3)

So, A'(11,9)

Now, a rotation of -180º is applied to point A'.

Let it becomes A''.

By a rotation of -180º, the coordinate gets changed by 2 quadrants.

A is in 1st quadrant because both x and y coordinates are positive.

A'' will be in 3rd quadrant where both x and y coordinates are negative.

Please refer to the attached image for the graphical representation of A, A' and A''.

So, the answer will be option A.
`(-11, -9)`.