This is solved in exactly the same way using exactly the same rule that was invoked in your other posting of a problem like this. (see https://brainly.com/question/11571563)
The product of near and far distances from the point of intersection of the secants to the circle is the same for both secants.
... 5×(5+x) = 6×(6+4)
... 5+x = 12 . . . . divide by 5
... x = 7 . . . . . . . subtract 5
