tolongin dong nih Tentukan nilai k yg memenuhi pernyataan brkt: a. garis 4y=kx-12 bergradien 4 b. garis yg melalui titik ( k,4 ) dan (-1,-3) bergradien -2

a) 4y = kx -12
y = ( kx -12)/4
y = (k/4)x
k/4 = 4
k = 16
b) (-3-4)/(-1-k) = -2
(-7)/(-1-k) = -2
-2(-1-k ) = -7
2 + 2k = -7
2k = -7-2
2k = -9
k = -9/2
k = -4 1/2