Odpowiedzi

2009-11-26T16:11:20+01:00
Zad 1
a
u = 4v
5u - v = 10
5 razy 4v - v = 10
20v - v = 10
19v = 10
v = 10/19
b
3r = s
3r + s = 24
s + s = 24
2s = 24
s = 24/2 = 12
zad 2
x + 3y = 3
x - y = 5
x = 3 - 3y
3 - 3y - y = 5
- 4y = 5 - 3
- 4y = 2
- y = 2/4
- y = 1/2
y = - 1/2
2009-11-26T16:13:17+01:00
1.a)
u = 4v/*(-5)
5u - v = 10
-5u = -20v
5u - v = 10
-5u + 20v = 0
5u - v = 10
__________
19v = 10 /: 19
v = 10/19

1.b)
3r = s /* (-1)
3r + s = 24
-3r + s = 0
3r + s = 24
_________
2s = 24 /:2
s = 12

2.
x + 3y = 3
x - y = 5
x + 3y = 3
-y = 5 - x / : (-1)
x + 3y = 3
y = -5 + x
x + 3(-5 + x) = 3
y = -5 + x
4x = 18 / : 4
y = -5 + x
x = 4,5
y = -5 + 4,5
y = 0,5


2009-11-26T16:13:44+01:00
Zad1 . Rozwiąż układ równań.

a) u = 4v
5u - v = 10
5u - 1/4u = 10
4 i 3/4u = 10 /: 4 i 3/4
u = 2 i 2/19
v = 1/4 * 2 i 2/19
v = 10/19

b) 3r = s
3r + 1/3r = 24
3r i 1/3r = 24 /: 3 i 1/3
r = 7 i 1/5 = 7,2
s = 1/3 * 7 i 1/5
s = 2 i 2/5 = 2,1

Zad 2. Rozwiąż układ równań metodą podstawiania.
x + 3y = 3
x - y = 5
x + 3y + x + y = 5 + 3
2x + 4y = 8