Using the sine rule,
[tex]\frac{\sin\text{ C}}{c}\text{ = }\frac{\sin \text{ D}}{d}[/tex]From the sketch,
D =90 d=25 c = 7
substitute the values into the formula
[tex]\frac{\sin\text{ C}}{7}=\frac{\sin 90}{25}[/tex]cross-multiply
[tex]25\text{ sin C = 7 sin90}[/tex][tex]25\text{ sin C=7}\times1[/tex]Divide both-side of the equation by 25
[tex]\sin C=\frac{7}{25}[/tex][tex]\sin \text{ C = 0.28}[/tex]
