Question
I. 2y² - 3y – 14 = 0 II. 3x² - 7x + 4 =
0 In the following questions, two equations numbered I and II are given. You have to solve both the equations and find out the correct option. Give answer if ;Solution
I. 2y² - 3y – 14 = 0 2y² - 7y  + 4 y – 14 = 0 y (2 y – 7) + 2( 2 y – 7) = 0 (y + 2) (2 y – 7) = 0 ∴ y = -2, 7/2 II. 3x² - 7x + 4 = 0 3x² - 4x - 3 x  + 4 = 0 x (3 x – 4) – 1 (3 x – 4) = 0 ∴ x = 1, 4/3 Hence, relationship cannot be established between x and y Alternate Method: if signs of quadratic equation is - ve and -ve respectively then the roots of equation will be -ve and +ve. (note: -ve sign will come in smaller root) So, roots of first equation = y = -2, 7/2 if signs of quadratic equation is - ve and +ve respectively then the roots of equation will be +ve and +ve. So, roots of second equation = x = 1, 4/3 After comparing we can conclude that relationship cannot be established.
1784.04 - 483.98 + 464.98 ÷ 15.06 = ?3
- What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exact value.)
(168.24 ÷ 23.98) x 19.81 + ? = 176.33
64.889% of 399.879 + √? = 54.90% of 799.80 – 44.03% of 400.21
A bag contains 25 white and some black balls. If the probability of drawing a black ball from the bag is thrice that of drawing a white ball, fin...
49.96% of 120.21 + √(15) ÷ 1.87 × 4.41 = ?Â
619.97 ÷ 20.01 X 124.99 ÷ 24.91 = ?
180.25 × 14.995 ÷ √26 = ? × 5.985
A number is first increased by 35% and then decreased by 35%. If the net change in the number is 302.5, then find the original number.