S What is the value of x?
9
0 12 units
16
15 units
X
0 20 units
R
0 25 units

9514 1404 393

  12 units

Step-by-step explanation:

In this geometry, all of the right triangles are similar, so corresponding sides are proportional.

  short-side/short-side = long-side/long-side

  9/x = x/16

  x^2 = 144 . . . . cross multiply

  x = 12 . . . . . . . take the square root

51

step-by-step explanation:

73-22=51 the   mass number minus the amount of protons gives you the amount of neutrons