Attempt following question by selecting a choice to answer.
B
Choose the coordinates of a point
(- 3, - 3) when the axes are turned through an angle
90°.c BA.
B(3, 3)
B.
B(3, - 3)
C.
B(- 3, 3)
D.
B(- 3, - 3)
B
C
Step 1: When the axes are turned through an angle θ, then the new coordinates in terms of original coordinates are x′ = x cos θ + y sin θ and y′ = -x sin θ + y cos θ.[Formula.]
Step 2: x′ = (- 3) cos 90° + (- 3) sin 90°[Substitute the values.]
Step 3: = (- 3)(0) + (-3)(1) = - 3
Step 4: y′ = -(-3) sin 90° + (-3) cos 90°[Substitute the values.]
Step 5: = (3)(1) + (-3)(0) = 3
Step 6: The new coordinates are (- 3, 3).