Tthe value of x is 20 u
To get the value of x from the diagram, we will use the triangle altitude theorem as shown below;
From the diagram;
9/RT = RT/16
RT^2 = 9*16
RT^2= 144
RT = 12
Get the value of x using the pythagoras theorm;
x^2 = 16^2 + 12^2
x^2 = 256 + 144
x^2 = 400
x = 20
Hence the value of x is 20 units
Learn more on pythagoras theorem here: link