Q. 144.4( 5 Votes )

# The sum of two nu

Answer :

Given: a + b = 15 To find: The value of a and b.

Method Used:

To solve the quadratic equation by factorisation method, follow the steps:

1) Multiply the coefficient of x2 and constant term.

2) factorise the result obtained in step 1.

3) Now choose the pair of factors in such a way that after adding or subtracting(splitting) them

You get coefficient of x.

Explanation:

Numbers are ‘a’ and ‘b’

According to given conditions:

a + b = 15

b = 15 – a …. (1)

Also, From (1),   15 × 10 = 3(15a – a2)

15 × 10 = 45a – 3a2

3a2 – 45a + 150 = 0

a2 – 15a + 50 = 0

a2 – 15a – 5a + 50 = 0

a (a – 10) – 5(a – 10) = 0

(a – 5) (a – 10) = 0

a = 5, 10

If a = 5, b = 15 – 5 = 10

If a = 10, b = 15 – 10 = 5

Hence, Numbers are 5,10 or 10, 5.

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation view all courses 