Find the value of the expression for the given replacement value.

[bumblebeetuna]

Hello,

I need help with the following problem:

Q) Find the value of the expression for the given replacement value: a=9

a²

---

1-a²

-So far I have (after replacing (a) with 9 and finding the following:

​

81

---

-80

-This is where I am stuck at. My teacher said it is wrong in that format but I am lost as to what to do next. Any assistance is greatly appreciated! Thank You!​

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