If ‘+’ means ‘–‘, ‘–‘ means ‘×’, ‘×’ means ‘÷’ and ‘÷’ means ‘+’, then what is he value of the following expression?

18 – 18  ÷ 3  – 72  × 12  + 4 – 6

I. 2^(x+2)+ 2^(-x)=5

II. (1/(y+1)+ 1/(y+5))=(1/(y+2)+ 1/(y+4))

I. 144x² - 163x - 65 = 0

II. 91y² - 128y -48 = 0

I. 3y² - 20y + 25 = 0

II. 3x² - 8x + 5 = 0

I. x² + 91 = 20x

II. 10y² - 29y + 21 = 0

I. 8a² – 22a+ 15 = 0

II. 12b² - 47b + 40=0

I. 63x²+ 148x + 77 = 0

II. 21y²+ 89y + 88 = 0

The quadratic equation (p + 1)x ² -  8(p + 1)x + 8(p + 16) = 0 (where p ≠ -1) has equal roots. find the value of p.

I. 3x² - 22 x + 40 = 0   

II. 4y² + 22y  + 24 = 0    

I. 2y² - 35y + 132 = 0

II. 2x² - 31x + 110 = 0

I. x²– 9x + 18 = 0

II. y²– 5y + 6 = 0