Answer:
x = 0
y = 5
z = -5.
Step-by-step explanation:
X-5y-z=-20
-2x-y-6z=25
-x-4y-z=-15
Add equation 1 and 3:
-9y - 2z = -35 .......... A
Multiply the first equation by 2:
2x - 10y - 2z = -40
Now add this to equation 2:
-11y -8z = -15.............B
Now multiply equation A by -4:
36y + 8x = 140.........C
Add equations B and C:
25y = 125
y = 5.
Substitute for y in equation A:
-9*5 - 2z = -35
2z = -45 + 35 = - 10
z = -5.
Now find x by substituting for y and z in the first equation:
x - 5(5) - (-5) = -20
x - 20 = -20
x = 0.
I believe it could be the third answer.
Answer:
x₁ = - 4 + √31
x₂ = - 4 - √31
Step-by-step explanation:
x² + 8x = 15
x² + 8x - 15 = 0
x = [- 8 ± √8² - 4×1×(-15)]/(2×1)
x = (-8 ± 2√31)/2
x₁ = (-8 ± 2√31)/2
x₁ = - 4 + √31
x₂ = - 4 - √31
Answer:
Graph is in the picture below
Step-by-step explanation:
The guys is lying he is gonna get your up 7373