Question

f(x)=ax+b find zeros by graphical method

Answer 1

Answer:

We begin with                      2x2 – 3x – 6 =     0,

            Divide both sides by 2,         x2 – 1.5x – 3 =      0

                                                            x2                     =     1.5x + 3

                                            \            x2 – 2x – 4      =     1.5x + 3 – 2x – 4

                                                                                    =      – 0.5x –1

                                            Let          y = x2 – 2x – 4       and          y = – 0.5x –1

            Therefore all we have to do is to draw the straight line  y = – 0.5x –1.

 

            The intersection of the given graph  y = x2 – 2x – 4 and this straight line is the solution.

            The graphs are shown below.

 

 

The L.H.S. shows that the intersection points are:

 

    (-1.1, -0.3) and (2.6, -2.3)

 

Therefore the roots of the equation:

    2x2 – 3x – 6 = 0

are       x = -1.1         and        x = 2.6

            (to 1 dec. place)

Step-by-step explanation: