CBSE Notes, Lectures

CBSE - Mathematics - Quadratic Equations

Quadratic Equations

NCERT Exercise Exercise 4.3

The difference of squares of two numbers is 180. The square of the smaller number is 8 times the larger number. Find the two numbers

Let the larger and smaller number be x and y respectively.
According to the question,
xy2 = 180 and y2 = 8x
⇒ x- 8x = 180
⇒ x- 8x - 180 = 0
⇒ x- 18x + 10x - 180 = 0
⇒ x(x - 18) +10(x - 18) = 0
⇒ (x - 18)(x + 10) = 0
⇒ x = 18, -10

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