Q1 of 168 Page 7

Check whether the following are quadratic equations:

(x − 3) (2x + 1) = x (x + 5)

Given; (x − 3) (2x + 1) = x (x + 2)

⇒ 2x2 + x − 6x − 3 = x2 + 5x


⇒ 2x2 + x − 6x − 3 − x2 − 5x = 0


⇒ x2 − 10x − 3 = 0


∵ The highest power of x in the equation is 2;


∴ It is a quadratic equation.


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