Question

If the product of the roots of the equation `x^2-3x+k=10`  is-2 then the value of k is
(a) -2 (b) -8 (c) 8 (d) 12   

Answer 1

(c) 8  

It is given that the product of the roots of the equation `x^2-3x+k=10 is -2` .  The equation can be rewritten as:

`x^2-3x+(k-10)=0`  

Product of the roots of a quadratic equation = `c/a` 

⇒` c/a=-2` 

⇒ `((k-10))/1=-2` 

⇒` k=8`