The sum of a square of a number and one less than the number equals nine less than the square of one more than the same number.. A). Write the mathematical expression, and B). Solve the unknown number.​

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Step-by-step explanation:

★Question★

The sum of a square of a number and one less than the number, equals nine less than, the square of one more than the same number. Find the number.

★Answer★

Let the number be 'x'.

Atq,

=> x² +x-1=(x+1)²-9

=>x²+x-1=x²+1+2x-9

=>x²-x²+x-2x-1-1+9=0.

=>x-7=0

.°. x =7.

20

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