If it has only one solution that means that there is only one value of x that will fulfill this equation
35 - 5x + 6x - 36 = -24 - 17x + 17x + 24
-5x + 6x - 36 = -24 -17x + 17x + 24 - 35
x - 36 = -24 + 24 - 35 (I just canceled out the 17x because it would have justy made the process longer if I moved them over)
x = -24 + 24 - 35 + 36
x = -35 + 36
x = 1
The answer to your question is 2.625
Answer : 35 brownies
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working:
3/5 = 21
1/5 = 21 / 3
1/5 = 7
5/5 = 7 x 5
1 (the amount of brownies she brought) = 35
Therefore, she brought 35 brownies