Question

Me ajude a resolver equaçoes a)x+2(y-4)=7 4(x+1)+y=29 b)3x+4(2-y)=2x

Answer 1

a)
x + 2(y-4) = 7
4(x+1) + y = 29

x = 7 - 2(y-4)
x = 7 - 2y + 8
x = 15 - 2y

Substitui na 2ª:
4(15-2y +1) + y = 29
64 - 8y + y = 29
-7y = -35
y = 5

x = 15 - 2*5
x = 5


b)
3x + 4(2-y) = 2x
3x + 8 - 4y = 2x
x - 4y = -8
x = 4y - 8

11 +3(x-1) = -y+1
11 + 3(4y - 8 - 1] = -y + 1
11 + 12y - 27 = -y + 1
13 y = 17
y = 17/11

x = 4y - 8
x = 4*17/11 - 8
x = 68/11 - 8
x = -20/11