Isolate the variable by dividing each side by factors that don't contain the variable I believe the correct answer is 1. c=ab-da
17+26 is different from 36+53 by if you add 17+26 the sum would be 43. And if you add 36+53 the sum would also be 89. So that means the way how they are different is that the 17+26 and 36+53 has different kinds of sums. They have different kinds of sums because you are different numbers.
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28 x 25 = $700
Answer: The class raises at least $700.