Answer:
(5,2,2)
Step-by-step explanation:
-3x+4y+2z = -3
2x-4y-z=0
y = 3x-13
Multiply the second equation by 2
2*(2x-4y-z)=0*2
4x -8y -2z =0
Add this to the first equation to eliminate z
-3x+4y+2z = -3
4x -8y -2z =0
-------------------------
x -4y = -3
Take the third equation and substitute it in for y
x - 4(3x-13) = -3
Distribute the 4
x - 12x +52 = -3
Combine like terms
-11x +52 = -3
Subtract 52 from each side
-11x +52-52 = -3-52
-11x = -55
Divide by -11
-11x/-11 = -55/-11
x=5
Now we can solve for y
y =3x-13
y =3*5 -13
y = 15-13
y=2
Now we need to find z
2x-4y-z=0
2(5) -4(2) -z=0
10-8 -z=0
2-z=0
Add z to each side
2-z+z= 0+z
2=z
x=5, y=2, z=2
(5,2,2)
Let p and w represent the speed of the plane and the speed of the wind, respectively.
.. speed = distance/time
.. p +w = 720/3 = 240
.. p -w = 720/4 = 180
Add the two equations to eliminate w.
.. 2p = 420
.. p = 210
.. w = p -180 = 30
The speed of the wind is 30 mph.
The speed of the plane in still air is 210 mph.
15 1/8 -1 3/5=
15 5/40 -1 24/40=
605/40 - 64/40=
541/40= 13 21/40
Answer:13 21/40
Answer:
B
Step-by-step explanation:
Because -1/2 is not a whole number so b is the only answer left
Answer:
-19x
Step-by-step explanation:
