Question

identify the rotation function mapping used to turn a (-7,4) to a (-4,-7). (1 point)
○ (x,y) → (y, x)
○ (x,y) → (x, -y)
○ (x,y) → (-y, x)
○ (x,y) → (2x, 2y)

Explanation:

Step1: Test option 1

$(x,y)\to(y,x)$ gives $(4,-7)
eq(-4,-7)$

Step2: Test option 2

$(x,y)\to(x,-y)$ gives $(-7,-4)
eq(-4,-7)$

Step3: Test option 3

$(x,y)\to(-y,x)$ gives $(-4,-7)=A'$

Step4: Test option 4

$(x,y)\to(2x,2y)$ gives $(-14,8)
eq(-4,-7)$

Answer:

C. $(x,y)\to(-y,x)$