Answer:
First choice.
Step-by-step explanation:
You could plug in the choices to see which would make all the 3 equations true.
Let's start with (x=2,y=-6,z=1):
2x+y-z=-3
2(2)+-6-1=-3
4-6-1=-3
-2-1=-3
-3=-3 is true so the first choice satisfies the first equation.
5x-2y+2z=24
5(2)-2(-6)+2(1)=24
10+12+2=24
24=24 is true so the first choice satisfies the second equation.
3x-z=5
3(2)-1=5
6-1=5
5=5 is true so the first choice satisfies the third equation.
We don't have to go any further since we found the solution.
---------Another way.
Multiply the first equation by 2 and add equation 1 and equation 2 together.
2(2x+y-z=-3)
4x+2y-2z=-6 is the first equation multiplied by 2.
5x-2y+2z=24
----------------------Add the equations together:
9x+0+0=18
9x=18
Divide both sides by 9:
x=18/9
x=2
Using the third equation along with x=2 we can find z.
3x-z=5 with x=2:
3(2)-z=5
6-z=5
Add z on both sides:
6=5+z
Subtract 5 on both sides:
1=z
Now using the first equation along with 2x+y-z=-3 with x=2 and z=1:
2(2)+y-1=-3
4+y-1=-3
3+y=-3
Subtract 3 on both sides:
y=-6
So the solution is (x=2,y=-6,z=1).
Y varies inversely with x
means that y=k/x
with x=0.7 and y=80
we have 80=k/0.7
k=0.7x80=56
so the equation is
y=56/x
Answer:give me brainlist
Step-by-step explanation:
Answer:
19.5
4555.555555555555 hz
Step-by-step explanation:
Answer:
y + 6 = (-8/5)(x - 1) in point-slope form
Step-by-step explanation:
Moving from the 1st point to the first, we see that x (the 'run') increases by 5 from -4 to 1, and y (the 'rise') decreases by 8. Thus, the slope of the line through these two points is m = rise / run = -8/5
Now we have two points on the line, plus the slope. Let's write out the point-slope formula for the equation of a straight line:
y - k = m(x - h), where (h, k) is a point on the line and m is the slope of the line.
Here, using the point (1, -6), we obtain:
y + 6 = (-8/5)(x - 1) in point-slope form