Q12 of 39 Page 141

When Rupa was born, his father was 25 years old. Form an equation and draw a graph for this data. From the graph find

(i) The age of the father when Rupa is 25 years old.


(ii) Rupa’s age when her father is 40 years old.

Give that, When Rupa was born, his father was 25 years old.

Now, let the age of Rupa’s father be ‘x’ and Rupa’s be ‘y.’


⇒ x - y = 25 is the equation.


For graph, we’ll first make the table of solutions by putting some random values of x and thereafter we’ll find corresponding values of y and then we’ll plot these points on graph, join them and extend them in straight line to find the graph.


(Note: ∵ equation is linear graph will always be straight line.)


Table of solutions for the given equation-



GRAPH:



(i) Given that y = 25.


∴ from the graph x = 50 (pt. E)


(ii) Given that x = 40


∴ from the graph y = 40 (pt. F) (; 15


(where, Father’s age = x and Rupa’s age = y)


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