Kopertina e librit Matematika 9

Zgjidhja e ushtrimit 2

Zgjidhja e ushtrimit 2 të mësimit 9B në librin Matematika 9 nga shtëpia botuese Botime Pegi me autorë Deborah Barton.


Pyetja

Zgjidhni ekuacionet e mëposhtme.

Zgjidhja

  1. 4(y1)3=32y4y43=32y4y7=32y4y+2y=3+76y=106y6=106y=534(y-1)-3=3-2y \rArr 4y-4-3=3-2y \rArr 4y-7=3-2y \rArr 4y+2y=3+7 \rArr 6y=10 \rArr \dfrac{\cancel6y}{\cancel6} = \dfrac{10}{6} \rArr y=\dfrac{5}{3}
  2. 3+4(2n1)=6n23+8n4=6n28n1=6n28n6n=2+12n=12n2=12n=123+4(2n-1)=6n-2 \rArr 3+8n-4=6n-2 \rArr 8n-1=6n-2 \rArr 8n-6n=-2+1 \rArr 2n=-1 \rArr \dfrac{\cancel2n}{\cancel2} = \dfrac{-1}{2} \rArr n=-\dfrac{1}{2}
  3. 42(x+2)=3(x5)42x4=3x152x=3x153x15=23x+2x=155x=155x5=155x=34-2(x+2)=3(x-5) \rArr 4-2x-4=3x-15 \rArr -2x=3x-15 \rArr 3x-15=-2 \rArr 3x+2x=15 \rArr 5x=15 \rArr \dfrac{\cancel5x}{\cancel5} = \dfrac{15}{5} \rArr x=3