SOLUTION: four years ago age of mother was three times the age of her daughter. write the linear equation to represent this situation and draw its graph

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Question 537019: four years ago age of mother was three times the age of her daughter. write the linear equation to represent this situation and draw its graph
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
Let the current age of the daughter be x
Let the current age of the mother be y
For years ago, their ages were x-4 and y-4 and we had
y-4=3%28x-4%29
That's the equation of a line in point-slope form. Its slope is 3, and it passes through the nonsensical point that indicates they are both 4 now and 4 years ago they were both zero years old and of course zero equals three times zero. There are many other points that do not make sense, but let's graph anyway.
We have that nonsense point and we could pick a more sensible one, (29, 79) for the case where four years ago the mother and daughter were 25 and 75 respectively.
graph%28+350%2C+450%2C+-5%2C+30%2C+-5%2C+85%2C+3x-8+%29