factorise the given photo
Attachments:
Answers
Answered by
19
To Find :-
- Factorise 21x² - 4√5x - 5 ?
Solution :-
Before Factorising Put The Equation Equal to Zero.
Now,
→ 21x² - 4√5x - 5 = 0
Splitting The Middle Term now, we get,
→ 21x² - 7√5x + 3√5x - 5 = 0
→ 7x(3x - √5) + √5(3x - √5) = 0
→ (3x - √5)(7x + √5) = 0
Putting Both Equal to Zero now, we get,
→ 3x - √5 = 0
→ 3x = √5
→ x = (√5/3).
Or,
→ (7x + √5) = 0
→ 7x = (-√5)
→ x = (-√5/7) .
Hence , x € { (√5/3) , (-√5/7) }.
Answered by
7
Factorising by Splitting middle term
By using Formula :-
On comparing the above questions with
We get,
a = 21. , b = -4√5. , c = -5
We know that,
D = b^2 - 4ac
From this we have
√D = √500 = 10√5
Now,
We have a formula to find zeroes of a quadratic polynomial
Put the above value in this formula, we get
Similar questions