Advertisements
Advertisements
Question
Solve the following equation by factorisation :
x(x + 1) + (x + 2)(x + 3) = 42
Advertisements
Solution
x(x + 1) + (x + 2)(x + 3) = 42
⇒ 2x2 + 6x + 6 – 42 = 0
⇒ x2 + 3x – 18 = 0
⇒ x2 + 3x – 18 = 0 ..(Dividing by 2)
⇒ x2 + 6x – 3x – 18 = 0
⇒ x(x + 6) 3(x + 6) = 0
⇒ (x + 6)(x – 3) = 0
Either x + 6 = 0,
then x = –6
or
x – 3 = 0,
then x = 3
Hence x = –6, 3.
APPEARS IN
RELATED QUESTIONS
Solve the following quadratic equations by factorization:
(2x + 3)(3x − 7) = 0
Solve the following quadratic equations by factorization:
`1/(x+4)-1/(x-7)=11/30` , x ≠ 4, 7
Determine two consecutive multiples of 3, whose product is 270.
An aeroplane take 1 hour less for a journey of 1200 km if its speed is increased by 100 km/hr from its usual speed. Find its usual speed.
Solve the following quadratic equation by factorisation.
7m2 = 21m
Write the set of value of 'a' for which the equation x2 + ax − 1 = 0 has real roots.
Solve the following equation: `"a"/("x" - "a") + "b"/("x" - "b") = (2"c")/("x" - "c")`
There is a square field whose side is 44m. A square flower bed is prepared in its centre leaving a gravel path all round the flower bed. The total cost of laying the flower bed and graving the path at Rs 2. 75 and Rs. 1.5 per square metre, respectively, is Rs 4,904. Find the width of the gravel path.
A two digit positive number is such that the product of its digits is 6. If 9 is added to the number, the digits interchange their places. Find the number.
The product of two successive integral multiples of 5 is 300. Then the numbers are:
