Question

One root of the quadratic equation (2x-3) (x+5)=0 is -5, then the other root is

A. 5
B.
-3
/2

C. 3
/2

D. 2/
3​

Answer 1

Answer:

Step-by-step explanation:

its not a method its just a basic logic

Answer 2

The value of the other root is 3/2. (Option C)

Given:

Equation: (2x-3) (x+5)=0

One root= -5

To find:

The other root

Solution:

The sum of roots can be obtained from the given equation.

Let the other root be X.

The given equation: (2x-3) (x+5)=0

2x(x+5)-3(x+5)=0

2$x^{2}$+10x-3x-15=0

2$x^{2}$+7x-15=0

Now, the coefficients of $x^{2}$, x, and the constant term are a, b, and c.

So, a=2, b=7, and c= -15.

The sum of the two roots= -b/a

= -7/2

The sum of roots = given root+ X

= -5+X

=X-5

On equating,

X-5= -7/2

X=5-7/2

X=(10-7)/2

X=3/2

Therefore, the value of the other root is 3/2.