Advertisements
Advertisements
Question
Solve the following equation by factorization
x2– 4x – 12 = 0,when x∈N
Solution
x2 – 4x – 12 = 0
⇒ x2 – 6x + 2x – 12 = 0
⇒ x (x – 6) + 2 (x – 6) = 0
⇒ (x – 6) (x + 2) = 0
Either x – 6 = 0, then x = 6
or x + 2 = 0, then x = -2
But -2 is not a natural number
∴ x = 6.
APPEARS IN
RELATED QUESTIONS
Solve the following quadratic equations by factorization:
`1/(x-1)-1/(x+5)=6/7` , x ≠ 1, -5
An aeroplane left 50 minutes later than its scheduled time, and in order to reach the destination, 1250 km away, in time, it had to increase its speed by 250 km/hr from its usual speed. Find its usual speed.
The perimeter of a rectangular field is 82 m and its area is 400 m2. Find the breadth of the rectangle.
Solve the following quadratic equations by factorization:
`x^2 – (a + b) x + ab = 0`
Solve the following quadratic equation for x:
`4sqrt3x^3+5x-2sqrt3=0`
Show that x = −3 is a solution of x2 + 6x + 9 = 0.
Solve the following equation: (x-8)(x+6) = 0
The sum of the square of 2 positive integers is 208. If the square of larger number is 18 times the smaller number, find the numbers.
In each of the following, determine whether the given values are solution of the given equation or not:
x2 + x + 1 = 0; x = 0; x = 1
Solve the following equation by factorization
`(x + 2)/(x + 3) = (2x - 3)/(3x - 7)`
