Q25 of 50 Page 4

Ravish tells his daughter Aarushi, “Seven years ago, I was seven times as old as you were then. Also, three years from now, I shall be three times as old as you will be.” If the present ages of Aarushi and Ravish are x and y years respectively, represent this situation algebraically.

Let the present ages of Aarushi and Ravish be x and y respectively.


Now,


Seven years ago,


Aarushi age = (x – 7)


Ravish age = (y – 7)


y – 7 = 7(x – 7)


y – 7 = 7x – 49


7x – y = 42


Now, according to second condition:


After 3 years,


Aarushi age = (x + 3)


Ravish age = (y + 3)


y + 3 = 3(x + 3)


y + 3 = 3x + 9


3x – y = -6


So, algebraically the equations can be written as


7x – y = 42


3x – y = - 6


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If the graph of 4x + 3y = 12, cuts the coordinate axes at A and B. And if O is the origin, find the hypotenuse of ΔAOB.

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Draw the graphs of the following linear equations on the same graph paper.

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