Question 257077
Solution  
you  have (x+2)(x+4)= 4(x)+ 88. 
x^2+6x+8=4x+88 (not eighty four as u assumed)
x^2+2x-80=0
x^2-8x+10x-80=0
x(x-8)+10(x-8)=0
(x+10)(x-8)=0
gives x=-10 or 8
take 8 as positive answer
0thers are 10 and 12 obviously
good day
cheers