Question

Oblicz miejsce zerowe funkci określonych wzorem :

1 y=3x-15

2 y=1/2x+4

3 y= -3x - 9

Answer 1

1) 3x-15=0

3x=15

x=5

 

2) 1/2x + 4=0

1/2x = -4

x = -8

 

3) -3x - 9 = 0

-3x = 9

x = -3

 

Answer 2

1.  f(x) = 0  <=> 3x-15 = 0

                          3x = 15 |:3

                             x = 5

2. f(x) = 0 <=> 1/2x + 4 = 0

                            1/2 x = -4| razy 2

                                   x = - 8

 

3. f(x) = 0 <=> -3x - 9 = 0

                          -3x = 9 |:(-3)

                               x = - 3

 

 

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