We will solve as follows:
*First: We will take the value on yards and write it as a single fraction, that is:
[tex]1\frac{1}{4}=\frac{4}{4}+\frac{1}{4}=\frac{5}{4}[/tex]*Second: We will transform the yards into inches, that is:
1 yard = 36 inches, so:
[tex]x=45[/tex]*Third: We will find the measure of the diagonal:
[tex]d=\sqrt[]{28^2+45^2}\Rightarrow d=53[/tex]So, the measure of the diagonal is 53 inches.