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.
JM
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