How to do middle term splitting
6x>2-7x-3
Answers
Answer:
Register
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Q. 10
5.0
( 2 Votes )
Factorize 6x
Class 8th
Answer
For factorizing, an expression split the middle term in such a way that the product of the coefficients of the new terms is equal to the product of the coefficients of the first and last terms in the expression.
Here, product of co–eff of first and last terms = 6 × (–3) = –18
So, if the middle term –7x is split into two terms say ax, bx, then a + b = –7 and ab = –18.
Observe that values –9 and 2 satisfy these equations.
6x2 – 7x – 3 = 6x2 – 9x + 2x – 3
We can write 6x2 = 3x × 2x and –9x = 3x × (–3)
6x2 – 9x + 2x – 3 = 3x × 2x + 3x × (–3) + 2x – 3
Observe that 3x is common for the first two terms and 1 is common for the next two terms.
⇒ 6x2 – 9x + 2x – 3 = 3x(2x – 3) + 1(2x – 3)
Now, (2x – 3) is the common term.
∴ 6x2 – 7x – 3 = (2x – 3)(3x + 1)
Hence, the factors of 6x2 – 7x – 3 are (2x – 3) and (3x + 1).