Jawabanmu

2014-05-27T10:34:27+07:00
Diket :
y =ax2 + bx +3
x = 2 gradien = -7
x = 5 gradien = 11
dit : a+b?
jwb :
y aksen = 2 ax + b
utk x = 2
-7 = 4a +b .....pers 1
utk x = 5
11 = 10a + b ...........pers 2

pers 1 & pers 2 dikurangi
4a + b = -7
10a + b = 11
shg
-6a = -18
a = 3

masukan dlm pers 1
4a + b = -7
12 + b = -7
b = -19

jadi a+b = 3-19 = -16