As the exercise says, the triangles are similar. So, we can set up proportions between correspondent sides.
In order to solve for x we can set up the proportion between the horizontal and vertical sides:

Solving this proportion for x implies 
Now you can solve for m and p using the pythagorean theorem, because both triangles are right:

Then, we know that the hypothenuse of the big triangle is m+p, so we have

which implies

I don't know but I know it is going to be a lot
ANSWER
For Jamal statement to be true,

EXPLANATION
The given statement is:
ax + b = a(x + c)
We expand the left hand side to obtain,
ax + b = ax + ac
Subtract ax from from both sides of the equation.
b=ac
We know that, a≠0 , so we can divide through by 'a'.

The answer is 90,000 because 10 to the power of 4 is 10,000 times 9 is 90,000