Advertisements
Advertisements
प्रश्न
Solve the following equation by factorization
5x2 – 8x – 4 = 0 when x∈Q
Advertisements
उत्तर
5x2 – 8x – 4 = 0
∵ 5 × ( – 4) = – 20
-20 = – 10 + 2
-8 = – 10 + 2
⇒ 5x2 - 10x + 2x - 4 = 0
⇒ 5x(x - 2) + 2(x - 2) = 0
⇒ (x - 2) (5x + 2) = 0 ...(Zero Product Rule)
Either x - 2 = 0,
then x = 2
or
5x + 2 = 0,
then 5x = -2
⇒ x = `-(2)/(5)`
∴ x = 2, `-(2)/(5)`.
APPEARS IN
संबंधित प्रश्न
Find the roots of the following quadratic equation by factorisation:
`2x^2 – x + 1/8 = 0`
A passenger train takes one hour less for a journey of 150 km if its speed is increased by 5 km/hr from its usual speed. Find the usual speed of the train.
Solve:
x(x + 1) + (x + 2)(x + 3) = 42
The sum of the squares of two consecutive positive integers is 365. Find the integers.
If 2 is a root of the quadratic equation \[3 x^2 + px - 8 = 0\] and the quadratic equation \[4 x^2 - 2px + k = 0\] has equal roots, find the value of k.
In each of the following, determine whether the given values are solution of the given equation or not:
`x = 1/x = (13)/(6), x = (5)/(6), x = (4)/(3)`
Solve the following equation by factorization
`(x - 3)/(x + 3) + (x + 3)/(x - 3) = 2(1)/(2)`
Solve the following equation by factorization
`sqrt(x(x - 7)) = 3sqrt(2)`
Paul is x years old and his father’s age is twice the square of Paul’s age. Ten years hence, the father’s age will be four times Paul’s age. Find their present ages.
Two years ago, a man’s age was three times the square of his daughter’s age. Three years hence, his age will be four times his daughter’s age. Find their present ages.
