SOLUTION: Please help. 1.Solve these using the multiplication principle. 9x = 90 -x = 42 -x/4 = 11 -3/5x = 12/35

Algebra ->  Inverses -> SOLUTION: Please help. 1.Solve these using the multiplication principle. 9x = 90 -x = 42 -x/4 = 11 -3/5x = 12/35       Log On


   

Question 132658: Please help.
1.Solve these using the multiplication principle.
9x = 90
-x = 42
-x/4 = 11
-3/5x = 12/35
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
I'll do the first two to get you started

# 1


9x=90 Start with the given equation



%281%2Fcross%289%29%29cross%289%29x=%281%2F%289%29%2990 Multiply both sides by 1%2F9 to isolate x. Note: 1%2F9 is the multiplicative inverse of 9



x=90%2F9 Multiply


x=10 Divide

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Answer:
So our answer is x=10






# 2



-x=42 Start with the given equation



%28-1%2Fcross%281%29%29cross%28-1%29x=%28-1%2F%281%29%2942 Multiply both sides by -1%2F1 to isolate x. Note: -1%2F1 is the multiplicative inverse of -1



x=%28-42%29%2F1 Multiply


x=-42 Divide

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Answer:
So our answer is x=-42