The answer to the expression is -97/20 or -4.85
B=3; C=16; and E=4096.
Using the information we have gives us

We know that:

We know that 2³ = 8, so B = 3.
To "undo" a square root, we square the number; 4²=16, so C = 16.
To "undo" a fourth root, we raise the answer to the fourth power; 8⁴ = 4096, so E = 4096.
We can express it at 5 (a+6)
This is easy. Select different values for x to find y values.
For example, let x = 0.
y = 8x + 12
y = 8(0) + 12
y = 0 + 12
y = 12
On your table, you have x = 0 and y = 12.
Do the same using other values of x.