tolong dibantu.
maaf fotonya kebalik
Tentukan penyelesaian persamaan”” berikut dengan cara pemfaktoran
1) x²+8x=0 => x(x+8)=0
x=0 dan x+8= 0
x = -8
{-8,0}
2) 7x²-21x=0 => 7x (x-3) = 0
= x (x – 3) = 0
x=0 dan x-3=0
x = 3
{0,3}
3) y²-64=0 => y² = 64
. y = ± 8
. y = 8 dan y= -8
. {-8,8}
4) 9y² – 49 = 0
=> 9y² = 49
y² = 49/9
y = ±7/3
y = -7/3 dan y = 7/3
{-7/3,7/3}
5) x²-5x-24=0
= x²+3x-8x-24=0
= x(x+3)-8(x+3)=0
= (x+3) (x-8) =0
= x+3=0 dan x-8=0
x=-3 x= 8
{-3,8}
6) x² – 16x + 15
= x²-x-15x+15=0
= x(x-1)-15(x-1)=0
= (x-1) (x-15) = 0
x=1 dan x = 15
{1,15}
7) 2x² + 3x – 35 = 0
= 2x²+10x-7x-35=0
= 2x(x+5)-7x-35=0
= 2x(x+5)-7(x+5)=0
= (x+5) (2x-7)
= x = -5. dan 2x-7=0 => 2x=7 =>x=7/2
{-5,7/2}
8) 6y²+7y-20=0
= 6y²+15y-8y-20=0
= 3y(2y+5)-8y-20=0
= 3y(2y+5)-4(2y+5)=0
= (2y+5)=0 (3y-4) =0
= 2y+5=0 3y-4 = 0
2y = -5 3y = 4
y= -5/2 y = 4/3
{-5/2, 4/3}
maaf kalo ada yg salah,
semoga membantu