Question

find the value of a minus b when a + b is equal to 9 and a b is equal to 20??​

Answer 1

Answer:

If a+ b is equal to 9 and ab is equal to 20,

Then a minus b can be 1 or -1

Step-by-step explanation:

Here given that

                                 

                          So,  

ert value of a in the first equation  a + b = 9

                                                     that is      

                                                                     

                                                                     

Rearranging the equation, we get            

This is like general quadratic equation

Where A is 1 , B is -9 and C is 20

Equation to find  b is

                                   

                               or        

Substitute of A ,B and C in first equation

                                     

                                   

    Similarly by substituting in second equation,

                                   

                                   

Hence b can be 5 or 4

When b is 5, a is

When b is 4, a is

Hence a-b can be

$5-4=1$

OrOrOrOrOr