Answer:
The width is 36.4 inches
Step-by-step explanation:
we know that
Applying teh Pythagorean Theorem
[tex]D^2=h^2+W^2[/tex]
where
D is the length of the diagonal of the television
W is the width
h is the height
substitute the given values
[tex]42^2=21^2+W^2[/tex]
solve for W
[tex]W^2=42^2-21^2\\W^2=1,323\\W=36.4\ in[/tex]