To perform a dilation of a point \((x, y)\) centered at the origin with a scale factor \(k\), you use the formula: \[ (x', y') = (kx, ky) \]
For point \(A(3, 7)\):
- Dilation with scale factor 2: \[ A' = (2 \cdot 3, 2 \cdot 7) = (6, 14) \]
For point \(B(4, 9)\):
- Dilation with scale factor 2: \[ B' = (2 \cdot 4, 2 \cdot 9) = (8, 18) \]
So the coordinates after dilation are: \[ A'(6, 14) \quad \text{and} \quad B'(8, 18) \]
Therefore, the correct response is: A′(6,14) and B′(8,18).