So firstly, plug in 19 into the x variable. [tex] f(19)=\frac{3}{19+2} -\sqrt{19-3} [/tex]
Next, solve the addition and subtraction on the denominator and within the square root. [tex] f(19)=\frac{3}{21} -\sqrt{16} [/tex]
Next, solve the square root [tex] f(19)=\frac{3}{21} -\frac{4}{1} [/tex]
Next, find the LCD of the two numbers (Which is 21 in this case) and multiply by the number it takes for the denominator to get to the LCD.
[tex] \frac{3}{21} *\frac{1}{1} =\frac{3}{21}\\ \\ \frac{4}{1} *\frac{21}{21} =\frac{84}{21} \\ \\ f(19)=\frac{3}{21} -\frac{84}{21} [/tex]
Subtract the fractions to get [tex] f(19)=-\frac{81}{21} =-\frac{27}{7} [/tex]
