I:2x – y + z = 7
II:x + 2y – 5z = -1
III:x – y = 6
you can first use III and substitute x or y to eliminate it in I and II (in this case x):
III: x=6+y
-> substitute x in I and II:
I': 2*(6+y)-y+z=7
12+2y-y+z=7
y+z=-5
II':(6+y)+2y-5z=-1
3y+6-5z=-1
3y-5z=-7
then you can subtract II' from 3*I' to eliminate y:
3*I'=3y+3z=-15
3*I'-II':
3y+3z-(3y-5z)=-15-(-7)
8z=-8
z=-1
insert z in II' to calculate y:
3y-5z=-7
3y+5=-7
3y=-12
y=-4
insert y into III to calculate x:
x-(-4)=6
x+4=6
x=2
so the solution is
x=2
y=-4
z=-1
Answer: 
Step-by-step explanation:
Since the center of dilation is not at the origin, we can use the following formula in order to find the coordinates of the vertices of the triangle D'E'F':
Where "O" is the center of dilation at (a,b) and "k" is the scale factor.
In this case you can identify that:
Therefore, susbtituting values into the formula shown above, you get that the coordinates ot the resulting triangle D'E'F, are the following:
Vertex D' → 
Vertex E' → 
Vertex F' → 
Answer:
1800 miles
Step-by-step explanation:
No. of miles driven by Mr. Thomas in May = 75
It is given that miles driven in July is 6 times of miles driven by Mr. Thomas in May(75 miles).
Thus
No. of miles driven by Mr. Thomas in July = 6 * No. of miles driven by Mr. Thomas in May = 6*75 = 450 miles.
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Another condition given that miles driven in June is 4 times of miles driven by Mr. Thomas in July(450miles as calculated above).
Thus
No. of miles driven by Mr. Thomas in June = 4 * No. of miles driven by Mr. Thomas in July = 4* 450 miles = 1800 miles.
No. of miles driven by Mr. Thomas in June is 1800 miles.
Since f(x) = -3x + 2, the slope of f(x) is greater than the slope of g(x).
Hence, the answer is (D).
