Question

Va rog am nevoie urgenta de subiectul 2 toate 3 exerciții. Am nevoie de rezolvarea completa. Dau coroană. Va rog sa ma ajutați. Maine ne pune nota pe exercițiile astea. ​

Answer 1

Răspuns:

Explicație pas cu pas:

1) 3x-4y+5=0

x=-3 => 3*(-3)-4y+5=0 => -4y-9+5=0 => -4y-4=0 => -4y=4 => y=-$\frac{4}{4}$ => y=-1

y=-1 => 3x -4*(-1)+5=0 => 3x+4+5=0 => 3x+9=0 => 3x=-9 => x=$\frac{-9}{3}$ => x=-3

x=0,6=> 3*0,6-4y+5=0 =>1,8 -4y+5=0=>6,8-4y=0=> 4y=6,8=> y=$\frac{6,8}{4}=> y=1,7$

$y=1,4=>3x-4*1,4+5=0=>3x-5,6+5=0=>3x-0,6=0=>3x=0,6=>x=\frac{0,6}{3}=>x=0,2$

$x=1+4\sqrt{2}=> 3*(1+4\sqrt{2})-4y+5=0=> 3+12\sqrt{2}-4y+5=0=>4y=8+12\sqrt{2} =>y=\frac{8+12\sqrt{2} }{4}=> y=2+3\sqrt{2}$

$y=a => 3x-4a+5=0=> 3x=4a-5=> x=\frac{4a-5}{3}$

2)

$x+\frac{5y-1}{3}=-\frac{2}{3} =>x=\frac{1-5y}{3}-\frac{2}{3} =>x=\frac{-1-5y}{3} =>\\-1-5y=3x=>5y=-1-3x=>y=\frac{-3x-1}{5}$

$\frac{2x+3}{2}-3y=10,5=> \frac{2x+3}{2}-3*(\frac{-3x-1}{5})=10,5=> \frac{2x+3}{2}+\frac{9x+3}{5}=10,5=> \frac{5*(2x+3)+2*(9x+3)}{10}=10,5=>10x+15+18x+6=105=>\\28x+21=105=>28x=105-21=>28x=84$

=>x=$\frac{84}{28} =3$

y=-2

3)

$\frac{a+1}{b}=\frac{1}{4} => 4*(a+1)=b=>4a+4=b$   1)

$\frac{a}{b+1} =\frac{1}{5}=>5a=b+1=>b=5a-1$     2)

Din 1) si 2) => 4a+4=5a-1=> 5a-4a=4+1=> a=5

b=4*5+4=24