Respostas
Explicação passo-a-passo:
a)
x + y = 22
x - y = 8
y = 22 - x
y = (22 - 1x)
x - 1(22 - x) = 8
x + (-22 + x) = 8
x - 22 + x = 8
2x = 30
x = 15
y = (22 -1 . 15)
y = (22 - 15)
y = 7
S = {(15, 7)}
b)
2x + y = 26
x - y = 4
2x + y = 26
x - y = 4
3x = 30
x = 10
-2x - y = -26
2x - 2y = 8
-3y = -18
y = 6
S = {(10, 6)}
c)
x + 2y = -4
3x - 2y = 20
2y = -4 - 1x
y = (-4 - 1x)/(2)
3x - 2(-4 - 1x)/(2) = 20
3x + (8 + 2x)/(2) = 20
6x + 8 + 2x = 40
8x = 32
x = 4
y = (-4 -1 . 4) / 2
y = (-4 - 4) / 2
y = -8/2
y = -4
S = {(4, -4)}
d)
3x + y = -5
5x - 2y = -1
6x + 2y = -10
5x - 2y = -1
11x = -11
x = -1
-15x - 5y = 25
15x - 6y = -3
-11y = 22
y = -2
S = {(-1, -2)}
Siga fundamentalmatematica no inst@gr@m
2)
2x + y = 30
5x - y = 40
y = 30 - 2x
y = (30 - 2x)/(1)
5x - 1(30 - 2x)/(1) = 40
5x + (-30 + 2x)/(1) = 40
5x - 30 + 2x = 40
7x = 70
x = 10
y = (30 -2 . 10)
y = (30 - 20)
y = 10
S = {(10, 10)}
2x + y = 30
5x - y = 40
2x + y = 30
5x - y = 40
7x = 70
x = 10
-10x - 5y = -150
10x - 2y = 80
-7y = -70
y = 10
S = {(10, 10)}
Resposta:
a)
x + y = 22
x - y = 8
y = 22 - x
y = (22 - 1x)
x - 1(22 - x) = 8
x + (-22 + x) = 8
x - 22 + x = 8
2x = 30
x = 15
y = (22 -1 . 15)
y = (22 - 15)
y = 7
S = {(15, 7)}
b)
2x + y = 26
x - y = 4
2x + y = 26
x - y = 4
3x = 30
x = 10
-2x - y = -26
2x - 2y = 8
-3y = -18
y = 6
S = {(10, 6)}
c)
x + 2y = -4
3x - 2y = 20
2y = -4 - 1x
y = (-4 - 1x)/(2)
3x - 2(-4 - 1x)/(2) = 20
3x + (8 + 2x)/(2) = 20
6x + 8 + 2x = 40
8x = 32
x = 4
y = (-4 -1 . 4) / 2
y = (-4 - 4) / 2
y = -8/2
y = -4
S = {(4, -4)}
d)
3x + y = -5
5x - 2y = -1
6x + 2y = -10
5x - 2y = -1
11x = -11
x = -1
-15x - 5y = 25
15x - 6y = -3
-11y = 22
y = -2
S = {(-1, -2)}
2)
2x + y = 30
5x - y = 40
y = 30 - 2x
y = (30 - 2x)/(1)
5x - 1(30 - 2x)/(1) = 40
5x + (-30 + 2x)/(1) = 40
5x - 30 + 2x = 40
7x = 70
x = 10
y = (30 -2 . 10)
y = (30 - 20)
y = 10
S = {(10, 10)}
2x + y = 30
5x - y = 40
2x + y = 30
5x - y = 40
7x = 70
x = 10
-10x - 5y = -150
10x - 2y = 80
-7y = -70
y = 10
S = {(10, 10)}