Question

What is the ordered pair of C′ after point C (1, 2) is rotated 90° clockwise?

Answer 1

Answer: (2,-1)

Explanation:

The rule for rotation of a shape about 90° clockwise is given by :-

`(x,y)\rightarrow(y,-x)` [i.e. interchange x by y and y by negative of x ]

Given point : C (1, 2)

When point C is rotated 90° clockwise , then the ordered pair for its image C' will be :-

`C(1,2)\rightarrow (2,-1)`

Hence, the ordered pair of C′ after point C (1, 2) is rotated 90° clockwise = (2,-1).

Answer 2

C'(2,-1)

Explanation:

1) Transform point C(1,2) to polar coordinates.

C(1,2)=C(x,y)=C(r,tetha)=C(squareroot(5),63.44Degrees)

2) Substract 90 degress to get C'

C'=(squareroot(5),-26.56)

3) Transform point C' to cartesian coordinates.

C'=(x,y)=(squarerott(5)cos(-26.56),squareroot(5)sin(-26.56)

=C'(2,-1)