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प्रश्न
If 3x + 5y = 9 and 5x + 3y = 7 find the value of x + y.
उत्तर
3x + 5y = 9 ........(1)
5x + 3y = 7 ........(2)
8x + 8y = 16 .............Adding (1) and (2)
x + y = 2 ............. dividing by 8
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Solution:
We need one of the solutions of the quadratic equation as 5.
Then we can take another root as any number like a positive or negative number or zero. Here I am taking another root of the quadratic equation as 2.
Then we can form a word problem as below,
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