Uji kompetensi A. Pilihlah jawaban yang benar di antara huruf A,B,C, dan D! No 1-10

1) ax + by + c = 0
2x + 4y - 7 = 0 ( B )

2) y = 2x - 1
ttk yg terletak (2,3) ( C )
pembuktian
x = 2 ----> y = 2(2) - 1 = 4 - 1 = 3

3) (x1,y1) = ( 0,0)
(x2,y2) = ( 2,2)
m = ( y2 - y1 ) / ( x2 - x1 )
m = ( 2 - 0) / ( 2 - 0)
m = 2/2
m = 1 ( A )

4) m = ( y2 - y1 ) / ( x2 - x1 )
m = ( 4 - 0) / ( 2 - 0)
m = 4/2
m = 2 ( A )

5) m = ( y2 - y1) / ( x2 - x1 )
m = ( 5 - 2) / ( 3 - 0)
m = 3/3
m = 1 ( D )

6) - 4x + 2y + 6 = 0
2y = 4x - 6
m = x/y
m = 4/2
m = 2 ( D)

7) 2x = y + 5
y = 2x - 5
m = 2
sejajar m1 = m2 = 2
pers garis
y - y1 = m ( x - x1 )
y - 3 = 2 ( x - 4)
y = 2x - 8 + 3
y = 2x - 5 ( D )

8) ( y - y1 ) / ( y2 - y1 ) = ( x - x1 ) / ( x2 - x1)
( y - 4) / ( 5 - 4 ) = ( x - 3) / ( 2 - 3)
( y - 4) / 1 = ( x - 3) / -1
- 1 ( y - 4) = 1 ( x - 3)
- y + 4 = x - 3
- y = x - 3 - 4
- y = x - 7
- x - y + 7 = 0
x + y - 7 = 0 ( C )

9) 3y = 2x + 27
m = ⅔
gradien tegak lurus
m1 . m2 = - 1
⅔ . m2 = - 1
m2 = - 1 ÷ ⅔
m2 = - 3/2
pers garis
y - y1 = m ( x - x1)
y + 3 = - 3/2 ( x + 2)
y = - 3/2 x - 3 - 3
y = - 3/2 x - 6 ( dikali 2)
2y = - 3x - 12
2y + 3x + 12 = 0
3x + 2y + 12 = 0 ( B)

10) x - y = 2
x + y = 4
------------------(-)
- 2y = - 2
y = 1
• x - y = 2
x + y = 4
---------------(+)
2x = 6
x = 3
hp ( 3,1 ) ( A )