If z = (x2 + 4x - 5) and y = (x2 + 3x - 4) , what is K if K is equivalent to z-1y ?

Question

If z = (x2 + 4x - 5) and y = (x2 + 3x - 4) , what is K if K is equivalent to z-1y ?

Answer 1

K is equivalent to z-1y:

 

   z:      x² + 4x - 5   

-1y:   -(x² + 3x - 4)

        ----------------

  K:               x  -  1

Answer 2

Hi Jeremy,

 

z= X² +4X-5                                                      y= X² +3X-4

  = X² +5X-1X-5... (using factorization)                  =X² +4X-1X-4 ..... (using factorization)

  = X(X+5)-1(X+5)                                               =X(X+4) -1(X+4)

  =(X+5)(X-1)                                                      =(X+4)(X-1) 

 

K is equivalent to z-1y= (X+5)(X-1) - 1(X+4)(X-1)

                                = (X-1){X+5-X-4}

                                = X-1

 

you can also do by subtracting y from z.

Answer 3

K= z- 1y 

  = x² +4x-5- (x²+3x- 4)= x² +4x-5- x²-3x +4) =x-1

 

K= x-1