Answer:
n = 2
Step-by-step explanation:
In order for the ratio to have a value of 1, the sum of exponents in the numerator must equal the sum of exponents in the denominator:
n + 7 = 9
n = 9 -7 . . . . . . subtract 7 from both sides of the equation
n = 2
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Alternatively, you can simplify the given expression:
![\dfrac{9^n(9^7)}{9^9}=1=\dfrac{9^n}{9^2}](https://tex.z-dn.net/?f=%5Cdfrac%7B9%5En%289%5E7%29%7D%7B9%5E9%7D%3D1%3D%5Cdfrac%7B9%5En%7D%7B9%5E2%7D)
Hopefully, it is clear to you that the value of n must be 2 in order to make the numerator equal to the denominator.
83.21.....................
Look at the attached picture⤴
Hope this will help u...:)
-4/(x + 1) = -1/(x + 5)
this is a proportion so we cross multiply
-1(x + 1) = -4(x + 5)
-x - 1 = -4x - 20
-x + 4x = -20 + 1
3x = -19
x = -19/3