[tex]a = {( \frac{2}{3} )}^{ - 2} - {( \frac{1}{2} )}^{ - 1} + ( - { \frac{1}{4} )}^{ - 2} [/tex]
[tex]a = {( \frac{3}{2}) }^{2} - 2 + {( - 4)}^{2} [/tex]
[tex]a = \frac{9}{4} - 2 + 16[/tex]
[tex]a = \frac{9}{4} + 14[/tex]
[tex]a = \frac{9}{4} + \frac{14}{1} [/tex]
[tex]a = \frac{9 \times 1 + 14 \times 4}{4 \times 1} [/tex]
[tex]a = \frac{9 + 56}{4} [/tex]
[tex]a = \frac{65}{4} [/tex]
