Answer:
12.75
Step-by-step explanation:
The computation of the geometric mean of sqrt 77 and sqrt 343 is given below:
As we know that
Geometric mean = 
where
a is the first number = 
And, the b is the second number = 
Now first we have to convert into a number
For a it, is = 8.78
And, for b, it is = 18.52
Now the geometric mean is

= 12.75
X would = 156. 4^2x would = 256 then subtract 100
3. y=112 this takes a lot of process of elimination so ill save you the paragraphs of numbers
second row - k³⁰/k¹⁴ - k¹⁶
third row - 12 ⁴⁵⁻²³ - 12²²
hope this helps