Substitute y=2x+4 into the first equation:
2x+(2x+4)=-8
4x+4=-8
4x=-12
x=-3
Substitute x=-3 into the second equation:
y=2(-3)+4
y=-2
Therefore, the solution is (-3, -2).
(2x+y=-8 y=2x+4)
3 answers
(10x+3y=-11 8x+2y=-6)
Multiply both sides of the second equation by -1 to make the y-coefficient negative:
-8x - 2y = 6
Now we have two equations:
10x + 3y = -11
-8x - 2y = 6
We can eliminate y by adding the equations:
2x = -5
Solving for x gives x = -5/2.
Substituting x = -5/2 into either original equation gives:
10(-5/2) + 3y = -11
-25 + 3y = -11
3y = 14
y = 14/3
Therefore, the solution is (-5/2, 14/3).
-8x - 2y = 6
Now we have two equations:
10x + 3y = -11
-8x - 2y = 6
We can eliminate y by adding the equations:
2x = -5
Solving for x gives x = -5/2.
Substituting x = -5/2 into either original equation gives:
10(-5/2) + 3y = -11
-25 + 3y = -11
3y = 14
y = 14/3
Therefore, the solution is (-5/2, 14/3).