Your answer is 18 because your dividing
So :

?
First, you want to bring everything together on the top of the fraction.
12=24/2 so you can have

Add like terms -- 12 +24 = 36

Now we are at

Which is the lowest possible simplified version while remaining at exact value.
Feel free to check my math! I kinda did this off the top of my head.
Answer:
FIRST PROBLEM:
Exact Form:
x = 25
/19
Decimal Form:
x = 1.31578947
Mixed Number Form:
x = 1 6
/19
SECOND PROBLEM
Exact Form:
x = −
9 + √
106
, −
9 −
√
106
Decimal Form: x = 1.29563014
, −
19.29563014
Step-by-step explanation: