Question

find the roots of quadratic equation by quadration formula x2-3
$x2 - 3 \sqrt{5x + 10 = 0}$
​

Answer 1

Answer:

3

5x

+10=0

We know that

Roots of quadratic equation ax

2

+bx+c=0 are given by

x=

2a

−b±

b

2

−4ac

or x=

2a

−b±

D

∴D=b

2

−4ac

⇒D=(−3

5

)

2

−4(1)(10)

⇒D=45−40=5

⇒

D

=

5

Now, x=

2a

−b±

D

⇒x=

2

3

5

±

5

⇒x

1

=

2

3

5

+

5

and x

2

=

2

3

5

−

5

⇒x

1

=

2

4

5

and x

2

=

2

2

5

⇒x

1

=2

5

and x

2

=

5

Hence, the roots of the given equation are 2

5

and

5