Answer:
Demetrius's account is $84 higher after the two transactions
Step-by-step explanation:
Let
x -----> original amount in Demetrius's account
y ----> amount in Demetrius's account after the deposit and the withdraws
we know that
The amount in Demetrius's account after the two transactions must be equal to the original amount in Demetrius's account plus the deposit minus the withdraws
so
therefore
Demetrius's account is $84 higher after the two transactions
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Explanation:
Plug in the lower bound of the domain, which is x = -3
f(x) = 3x+2
f(-3) = 3(-3)+2
f(-3) = -9+2
f(-3) = -7
If x = -3, then the output is y = -7. Since f(x) is an increasing function (due to the positive slope), we know that y = -7 is the lower bound of the range.
If you plugged in x = 5, you should find that f(5) = 17 making this the upper bound of the range.
The range of f(x) is -7 < y < 17
Recall that the domain and range swap places when going from the original function f(x) to the inverse
This swap happens because how x and y change places when determining the inverse itself. In other words, you go from y = 3x+2 to x = 3y+2. Solving for y gets us y = (x-2)/3 which is the inverse.
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In short, we found the range of f(x) is -7 < y < 17.
That means the domain of the inverse is -7 < x < 17 since the domain and range swap roles when going from original to inverse.