If (4, -9) is rotated 270o about the origin the new point would be: A.
(-9, 4)

B.
(-9, -4)

C.
(9, 4)

D.
(-4, 9)

Strategy 1: To transport 1/42 to the other side, take a reciprocal of it and becomes 42. To get the value x, this 42 is multiplied by 3/7. That is
x = 42*(3/7) = 126/7 = 18

Strategy 2: To cancel 1/42 beside x, you multiply by 42 on both sides.
[(1/42)*x]*42 = 42*(3/7)
x = 126/7
x = 18