Question

Реши систему уравнений

Answer 1

Ответ:

5)

$\left \{ {{2u+3v=11} \atop {-2u+5v=13}} \right.$

$\left \{ {{2u=11-3v} \atop {-2u+5v=13}} \right.$

$-(11-3v)+5v=13 = > v=3$

$-2u+15=13 = > u=1$

Ответ: V=3; U=1

6)

$\left \{ {{3s-4t=-24} \atop {5s+4t=24}} \right.$

$\left \{ {{3s-4t=-24} \atop {4t=24-5s}} \right.$

$3s-(24-5s)=-24 = > s=0$

$4t=24-0 = > t=6$

Ответ: S=0; T=6

7)

$\left \{ {{4x+3y=-5} \atop {7x+3y=-11}} \right.$

$\left \{ {{3y=-5-4x} \atop {7x+3y=-11}} \right.$

$7x-5-4x=-11 = > x=-2$

$-14+3y=-11 = > y=1$

Ответ: X=-2; Y=1

8)
$\left \{ {{12a+5b=65} \atop {9a+5b=50}} \right.$

$\left \{ {{12a+5b=65} \atop {5b=50-9a}} \right.$

$12a+50-9a=65 = > a=5$

$5b=50-45 = > b=1$

Ответ: A=5; B=1