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20 votes
20 votes
9(m - 3) + 3m = 7m + 43

User Chintan Thakar
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1 Answer

22 votes
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\begin{gathered} 9(m-3)+3m=7m+43 \\ \text{Multiply the parenthesis by 9 and you have} \\ \\ (9* m-9*\lbrack-3\rbrack)+3m=7m+43 \\ \text{Next you have} \\ 9m-27+3m=7m+43 \\ \text{Note that the 9 multiplies the m to get 9m,} \\ \text{and the 9 also multiplies the negative 3 to arrive at negative 27.} \\ \text{After applying 9 to open the parenthesis, you now have } \\ 9m-27+3m=7m+43 \\ \text{You collect like terms. In this case all expressions that have m are like terms} \\ \text{The ones that does not have m are also like terms but, separate} \\ \text{Collect like terms with m on to the left hand side} \\ 9m+3m-7m=43+27 \\ \text{Note that whenever a positive number moves over across the sign of equality,} \\ it\text{ becomes a negative number and vice versa.} \\ \text{Hence 7m has moved and now becomes -7m} \\ \text{Also -27 has moved and now becomes +27} \\ 9m+3m-7m=43+27 \\ 5m=70 \\ \text{Divide both sides by 5 to eliminate it from the left side} \\ \text{and hence m would now stand alone} \\ (5m)/(5)=(70)/(5) \\ m=14 \end{gathered}

User Ksohan
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