Tugas Aljabar Linear

1. 2x + 5y = 2

        4x + y  = 3

Di eliminasikan

2x + 5y = 2  4

4x +   y = 3  2

8x + 20y =   8

8x + 2y   =   6

         8y   =   2

           Y    =  2      =   1

                     8           4

2x + 5y = 2

2x + 5(1/4) = 2

2x + 5/4 = 2

2x = 2 -5/4

X = 2 -5/4

           2

Titik potong = (2 -5/4 , -1 )

                          (       2      4 )

2.A ( -3,5 ) dengan gradien  4

Jawab :

             Y = mx + b

             Y –y₁ = m (x – x₁)

 

Y – (5)            =  4 x – (-3)

 

Y -  5              =  4   x + 3

Y – 5              =  4x + 12

Y                     = 4x + 12 + 5

Y                     = 4x + 17

                 

3.A ( -2,5) , B (3, -11). M = 2

Y – y1   =   x-x1

Y2-y1        x2-x1

y-5        =   x-(-2)

-11-5         3-(-2)

y-5         =   x+2

-16              3+2

y-5         =  x+2

-16               5

5(y-5)   = -16(x+2)

5y-25    =-16x-32

5y        =-16x-32+25

                    2

5y        =-16x-7

Y          =-16x-7

                  5

Gambar 1

Gambar 2

Gambar 3