Question

solve the system
5x -5z=10
7x - 2y + 4z =35
3x +2y =-85


2) 3x + 2y - z = -7
y + 5z =-29
2x-2y = 2

Answer 1

http://www.twiddla.com/865824

Answer 2

question 2)reduce the first equation in two a form with 2 variable and solve the resulting equations simultaneously
2x-2y=2
2x=2+2y
x=1+y
substitute x in 1,you'll have 3(1+Y)+2y-z=-7
3+3y+2y-Z=-7
5y-z=-10
now solve 5y-z=-10 and y +5z=-29
you'll get y=-79/26 and x=-53/26
substitute y in y+5z=-29 to get the value of z
-79/26+5z=-29
z=-135/26
try question 1

Answer 3

5x -5z=10 _____1
7x - 2y + 4z =35___2
3x +2y =-85____3

3+2=

7x-2y+4z=35
3x+2y=-85
10x+4z=-50_____4
2(1)

10x-10z=20

4-1
10x+4z=-50
-10x+10z=-20
14z=-70
z=-5
now subsitute this in equation 1
5x-4(5)=10
x=6
now kindly do the same for y urself