Answer:
(-6,9,-3)
Step-by-step explanation:
-3x -y +z=6
-3x-y+3z =0
x-3z =3
Multiply the second equation by -1
-1 *(-3x-y+3z) =0*-1
3x +y -3z =0
Add this to the first equation
-3x -y +z=6
3x +y -3z =0
----------------------
0 + 0 + -2z = 6
Divide by -2
-2z/-2 = 6/-2
z = 6/-2
z=-3
Take the third equation to find x
x-3z=3
x-3(-3) = 3
x+9=3
Subtract 9 from each side
x+9-9 =3-9
x=-6
Now we need to find y
3x +y -3z =0
3(-6) +y -3(-3) =0
-18 +y +9=0
-9+y =0
Add 9 to each side
-9+9+y = 0+9
y=9
(-6,9,-3)
Step-by-step explanation:
(-1,0),m=2
(1-7),m=12
m=-4,(-1,-4)
9514 1404 393
Answer:
6x^2 +x -12
Step-by-step explanation:
Substitute for A and B and collect terms.
2B +3A
= 2(3x^2 -x +3) +3(x -6) . . . . substitute for A and B
= 6x^2 -2x +6 +3x -18 . . . . . eliminate parentheses
= 6x^2 +x -12 . . . . . . . . . . . . collect terms
60 min = 1 hour
30 times 2 = 60
7.7 times 2 = 15.4
the avg speed is 15.4 km an hour
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