Question

Please tell me the number four and five instructions are solve the system of simultaneously equation by using the substitution method 100 points please help

Answer 1

1) x = 2 and y = -2

2) x = 6 and y = 5

3) x = 2 and y = -4

Explanation:

1) 3x + y = 4

since y = -x subtitute it in the equation

3x + (-x) = 4

3x - x = 4

2x = 4

x = 4\2

x = 2

y = -2

2) 4x - y = 19

since y = x - 1 subtitute it in the equation

4x - (x - 1) = 19

4x - x + 1 = 19

3x = 19 - 1

3x = 18

x = 18\3

x = 6

y = 6 - 1 = 5

3) y = 3x - 10

y - 3x = -10

since 2x + y = 0

thus y = -2x subtitute in equation

-2x - 3x = -10

-5x = -10

x = -10\-5

x = 2

y = -2 * 2 = -4

Answer 2

4. 3x+(-x)=4
3x-x=4
2x=4
x=4/2
answers:
x=2
y=-2


5.
y=x-1
4x-y=19
-x+y=-1
4x-y(cross the y’s out they cancel eachother)=19
3x=18
x=6
-6+y=-1
y=-1+6
y=5
answers:
x=6
y=5