SOLUTION: A two-digit number is the same as the number with its digits reversed increased by three times the original number's unit's digit. If five times the sum of the digits is 70, find t

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: A two-digit number is the same as the number with its digits reversed increased by three times the original number's unit's digit. If five times the sum of the digits is 70, find t      Log On


   



Question 253278: A two-digit number is the same as the number with its digits reversed increased by three times the original number's unit's digit. If five times the sum of the digits is 70, find the original number. (find a system of two equations then use the system to find the original number).
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
10x+y=10y+x+3y
10x-x+y-10y-3y=0
9x-12y=0 multiply by -5
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5(x+y)=70
5x+5y=70 multiply by 9 & add
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-45x+60y=0
45x+45y=630
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105y=630
y=630/105
y=6 answer for the tens digit in the original number.
5(x+6)=70
5x+30=70
5x=70-30
5x=40
x=40/5
x=8
Proof:
10*8+6=10*6+8+3*6
80+6=60+8+18
86=86