plz solve this question (by completing square method) plz mark brainlist
Answers
1.
x² - 3x- 10 use (b/2)² = 9/4
x² - 3x + 9/4 - 10 - 9/4
(x - 3/2)² = (7/2)²
x - 3/2 = + 7/2
x = 3/2 + 7/2 x = 3/2 - 7/2
x = 10/2 x = -4/2
x = 5, -2
2.
2x² + x - 6
2(x² + x/2 - 6) (1/2 of 1/2 = 1/4 (1/4)² = 1/16
2(x² + x/2 + 1/16- 3 - 1/16)
2[(x + 1/4)² - (49/16)²]
2[(x+ 1/4) - 2(+7/4)]
2x + 2/4 - 14/4 2x + 2/4 + 14/4
2x - 12/4 2x + 16/4
2x = 3 2x = -4
x = -2, 3/2
3.
√2x² + 7x + 5√2
√2(x² + 7x/√2 + 5) (7/√2x 2) = 49/8
√2(x² + 7x/√2 + 49/8 + 5 - 49/8)
√2 [(x + 7/2√2)² + (9/8)²
√2[(x+7/2√2) + 3/2√2]
√2x + 7/2 + 3/2
√2x + 7/2 + 3/2 √2x +7/2 - 3/2
√2x = - 5 √2x = - 2
x = -5/√2, - √2
4.
2x² - x + 1/8 = 0
2(x²- x/2 + 11/16 = 0 1/2 of 1/2 = 1/4 (1/4)² = 1/16
2[x²- x/2 + 1/16 + 1/16 - 1/16 = 0
2[(x - 1/16)² + 0] = 0
2(x-1/4)
2x = 1/2
X = 1/4
5.
100x² - 20x + 1 = 0
100{x² - x/5 + 1/100 = 0 ( 1/5 x 2) = 100
100[(x² - x/5 + 1/100 + 1/100 - 1/100)]
100[(x - 1/10)² - 0]
100(x - 1/10 + 0)
100x - 10
x = 1/10
Dear!
