Answer:
1. B 2. C
Step-by-step explanation:
1. x^2-18x+(18/2)^2=19+(18/2)^2
(x-18/2)^2=100
(x-9)^2=100
x1= -1 x2= 19
2. x^2=81
x=+-9
x1=-9 x2=9
Answer:
C
Step-by-step explanation:
Here, we want to know if the table represents a proportional relationship
Looking at the table, if we multiply the x-terms by -4, we get the y-terms
So the answer here is that Yes, because all the ratios of y to x are equal to -4
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)
