Aftab tells his daughter Seven years ago, I was seven times you were then also three years from now ,I shall be three times as old as you will be. Find their ages
Answers
Answer:
Given: Seven years ago, Aftab was seven times as old as his daughter and after 3 years Aftab will be 3 times as old as his daughter.
To Represent the situations algebraically and graphically we need to find the linear equations for these situations.Let present age of Aftab = x
Let present age of his daughter = y
Then, seven years ago the age of Aftab and his daughter must have been seven less than their present ages,Age of Aftab seven years ago = x – 7
Age of Daughter seven years ago = y – 7
According to the question,
Seven years ago, Aftab was seven times as old as his daughter, So
x - 7 = 7(y - 7)
⇒ x - 7 = 7y - 49
⇒ x = 7y - 42
Now for finding different points of this equation, we can either take different values of x and put them in the equation to obtain values of y or vice versa
Putting y = 5, 6 and 7 in equation (¡),
we get,
For y = 5,
x = 7 × 5 – 42
= 35 – 42 = -7For x =6,
x = 7 × 6 – 42
= 42 – 42= 0For y = 7,
x = 7 × 7 – 42
= 49 – 42 = 7
Thus we got 3 points to plot on graph for this equation.
Three years from now,
Age of Aftab = x+3
Age of Daughter = y+3
According to the question,
⇒ x + 3 = 3(y + 3)⇒ x + 3 = 3y + 9⇒ x = 3y + 6
Now for finding different points of this equation, we can either take different values of x and put them in equation to obtain values of y or vice versa
Putting x = 0, 3 and 6
Thus we got 3 points to plot on graph for this equation.
Algebraic representation
x - 7y = -42 (i)
x - 3y = 6 (ii)
Answer:
