If the television set measures 33 inches diagonal, the screen width is going to be 26.4 inches. You can find the answer by using the Pythagorean theory.
screen length equals = x
height equals ).75x
(0.75x)^2+x^2= the diagonal d^2
1.5625x^2=33^2
and then x^2= 696.96
x= 26.4