Respuesta :
Answer: x=-2 y=13
2(-2)+1=-3 check
-2-2=-4 check
Step-by-step explanation:
Horner's method:
2 1 -3
1 -2 -4
delta = det(
2 1
1 -2) = 2×-2 - 1 = -5
x = det(
-3 1
-4 -2)/-5 = (-2×-3-1×-4)/-5 = -2
y = det(
2 -3
1 -4)/-5 = (-8+3)/-5 = 1
Or by elimination
x = 2y - 4 from adding 2y=2y to second eqn
2(2y-4)+y=-3 by substituting for x in first.
4y-8+y=-3
5y=8-3=5
y=1
x=2y-4=2-4=-2
Answer:
(-2,1)
Step-by-step explanation:
2x + y = -3
x - 2y = -4
Multiply the first equation by 2 so we can eliminate y
2(2x + y = -3 )
4x +2y = -6
Add the second equation
4x +2y = -6
x - 2y = -4
-------------------
5x = -10
Divide by 5
5x/5 = -10/5
x = -2
We still need to find y
2x + y = -3
Substitute x in
2(-2) +y = -3
-4 +y = -3
Add 4 to each side
-4+4 +y = -3+4
y = 1