Find the value of the expression for the given replacement value.
-$\frac { a ^ { 2 } } { 1 - a ^ { 2 } } ; a = 9$
A) $\frac { 81 } { 82 }$
B) $- \frac { 81 } { 80 }$
C) $- \frac { 80 } { 81 }$
D) $\frac { 81 } { 80 }$

Question

Find the value of the expression for the given replacement value.
-$\frac { a ^ { 2 } } { 1 - a ^ { 2 } } ; a = 9$
A) $\frac { 81 } { 82 }$
B)  $- \frac { 81 } { 80 }$
C) $- \frac { 80 } { 81 }$
D) $\frac { 81 } { 80 }$

Quizplus · Accepted Answer

Substituting $a = 9$ into the expression gives $\frac{9^2}{1 - 9^2} = \frac{81}{1 - 81} = \frac{81}{-80} = -\frac{81}{80}$.

Find the Value of the Expression for the Given Replacement a21−a2;a=9\frac { a ^ { 2 } } { 1 - a ^ { 2 } } ; a = 91−a2a2​;a=9

Find the Value of the Expression for the Given Replacement $\frac { a ^ { 2 } } { 1 - a ^ { 2 } } ; a = 9$