Diketahui garis l bergradien -1/2 dan melalui titik (2,-3). Jika titik (a,5) dan (-1,b) terletak pada garis l, tentukan nilai a+b

cari persamaan garisnya
y - y1 = m(x - x1)

m = -1/2
x1 = 2
y1 = -3

y - y1 = m(x - x1)
y - (-3) = -1/2 (x - 2)
y + 3 = -x/2 + 1
y = -x/2 + 1 - 3
y = -x/2 - 2

(a,5)
5 = -a/2 - 2
5+2 = -a/2
7 = -a/2
7 x 2 = -a
14 = -a
a = -14

(-1,b)
b = -(-1)/2 - 2
b = 1/2 - 2
b+2 = 1/2
2(b+2) = 1
2b + 4 = 1
2b = 1 - 4
2b = -3
b = -3/2


(-14,5), a = -14
(-1,-3/2), b = -3/2

-14 + -3/2
= -28/2 + -3/2
= -31/2
= -15 -1/2

maaf kalo salah