Quadratic equation
Class 10th (CBSE)
Solve it neatly
Answers
Answer:
I used product sum method to find factors.
It won't affect your marks in anyway.
EXPLANATION.
Roots of the quadratic equations,
(1) = x² - 3x - 10 = 0.
Factorizes into middle term split, we get.
⇒ x² - 5x + 2x - 10 = 0.
⇒ x(x - 5) + 2(x - 5) = 0.
⇒ (x + 2)(x - 5) = 0.
⇒ x = -2 and x = 5.
(2) = 2x² + x - 6 = 0.
Factorizes into middle term split, we get.
⇒ 2x² + 4x - 3x - 6 = 0.
⇒ 2x(x + 2) -3(x + 2) = 0.
⇒ (2x - 3)(x + 2) = 0.
⇒ x = 3/2 and x = -2.
(3) = √2x² + 7x + 5√2 = 0.
Factorizes into middle term splits, we get.
⇒ √2x² + 5x + 2x + 5√2 = 0.
⇒ x(√2x + 5) +√2(√2x + 5) = 0.
⇒ (x + √2)(√2x + 5) = 0.
⇒ x = -√2 and x = -5/√2.
(4) = 2x² - x + 1/8 = 0.
Take L.C.M in this equation we get.
⇒ 16x² - 8x + 1 = 0.
Factorizes into middle term splits, we get.
⇒ 16x² - 4x - 4x + 1 = 0.
⇒ 4x(4x - 1) - 1( 4x - 1) = 0.
⇒ (4x - 1)(4x - 1) = 0.
⇒ (4x - 1)² = 0.
⇒ x = 1/4.
(5) = 100x² - 20x + 1 = 0.
Factorizes into middle term splits, we get.
⇒ 100x² - 10x - 10x + 1 = 0.
⇒ 10x(10x - 1) - 1(10x - 1) = 0.
⇒ (10x - 1)(10x - 1) = 0.
⇒ (10x - 1)² = 0.
⇒ x = 1/10.