A= B+C/D, so B+C= AxD.
And so, we have an addition sentence (A+B) equals a sum (AxD). Every time we have two addends equals a sum, we know that by subtracting one of the addend from the sum we will obtain the value of the remaining addend since they both constitute the sum. Therefore, (AxD)-C=B, so we can easily write the solution for B; B= (AxD)-C.
B= (AxD)-C.
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