math
posted by jenny .
If the answer is 12/3m what is the question>
How can you solve equations like these?
9r + 7 = 4r  8
Need to get the r on one side.
1st subtract 4r from the right side of the = sign. What you do to one side do to the other. 9r4r+7=4r4r8. 5r+7=8
2nd subtract 7 from the left side to get r's by themselves. 5r+77=87....5r=15.
Divide 5r by 5.....remeber do it to both sides......5r/5=15/5......r=3
check answer.
9(3)+7=4(3)8....27+7=128............20=20
Thanks for your help. I'm completely lost. Can you explain how 9r+7 = 4r8?
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