Explanation:
step one:
The question is incomplete it did not specify weather the scale was a reduction or an increase in the dimension of the rectangle.
step two:
let us assume it was to be an increase i.e 7x
the length would be 4*7= 28 inches
the width would be 6*7= 42 inches
step three:
Also, we assume it was to a decrease i.e 7x
the length would be 4/7= 0.57 inches
the width would be 6/7= 0.85 inches