Here the centre of dilation is (0,0) and the point is (3,4) and the scale factor is 7 .
To find the image after the dilation, we need to multiply each coordinate by the scale factor that is 7 . And on multiplying we will get, 3 times 7=21 and 4 times 7=28.
THerefore the point that we get after dilation is (21,28) .