e^2x - 5e^x = 24
(e^x)^2 - 5e^x =24
let e^x = u
u^2 - 5u = 24
u^2 -5u - 24 =0
(u - 8)(u+3)=0
u = 8 or u = -3
since e^x = u then u can't equal -3
e^x = 8
by taking ln for both sides
ln(e^x) = ln(8)
xln(e) = ln(8) .......................ln(e) = 1
x = ln(8) = 3ln(2)
