Show that (4x – 5)^2 – 5x(3x – 8) is positive for all values of x

(4x-5)^2-5x(3x-8)

(16x^2-40x+25)-(15x^2-40x)

16x^2-15x^2-40x+40x+25

x^2+25

if x = positive, x^2 will be positive.

if x = negative, x^2 will be positive.

x^2 is positive for all values of X, +25 will not make it negative.