Q. 14.7( 3 Votes )
Obtain a pair of linear equations in two variables from the following information:
Father tells his son, "Five years ago, I was seven times as old as you were. After five years, I will be three times as old as you will be".
Answer :
Let the present age of father = x
Let the present age of son = y
Now,
Given, Five years ago, father was seven times as old as son.
⇒ (x–5) = 7(y–5)
x – 5 = 7y – 35
= x – 7y + 30 = 0 …[1]
Also, after five years, father will be three times as old as son
⇒ (x + 5) = 3(y + 5)
x + 5 = 3y + 15
= x – 3y – 10 = 0 …[2]
eq[1] and eq[2] are required equations
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