Answer:
x=4
Step-by-step explanation:
Since both triangles are similar, you can make an equation 12/5x-2 = 16/6x. When you cross multiply you get 72x=80x-32. Then you transfer the 80x and you get -8x = -32. Then you divide by -8 and you get x=4.
the assumption being that the first machine is the one on the left-hand-side and the second is the one on the right-hand-side.
the input goes to the 1st machine and the output of that goes to the 2nd machine.
a)
if she uses and input of 6 on the 2nd one, the result will be 6² - 6 = 30, if we feed that to the 1st one the result will be √( 30 - 5) = √25 = 5, so, simply having the machines swap places will work to get a final output of 5.
b)
clearly we can never get an output of -5 from a square root, however we can from the quadratic one, the 2nd machine/equation.
let's check something, we need a -5 on the 2nd, so

so if we use a "1" as the output on the first machine, we should be able to find out what input we need, let's do that.

so if we use an input of 6 on the first machine, we should be able to get a -5 as final output from the 2nd machine.

Distribute the 5 to the (2+y). Parenthisis always come first. after that combine the 5y and the -y. you should end up with 2-(+4y) +2. add the -2 and +2. you should be left with 4y
170° is the answer I got hope it helps