SOLUTION: Solving problems involving systems of linear equations in two variables: three years ago, rica was thrice as old as dandy. three years hence, she will be twice as old. find thei

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Question 1102873: Solving problems involving systems of linear equations in two variables:
three years ago, rica was thrice as old as dandy. three years hence, she will be twice as old. find their present ages.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Three years ago,
R-3=3%28D-3%29
R-3=3D-9
1.R-3D=-6
.
.
.
Three years from now,
R%2B3=2%28D%2B3%29
R%2B3=2D%2B6
2.R-2D=3
.
.
Subtract eq. 2 from eq. 1,
R-3D-%28R-2D%29=-6-3
R-3D-R%2B2D=-9
-D=-9
D=9
Now use either equation to solve for R.