Answer:
x = -0.6
y = 2.2
z = 2
Step-by-step explanation:
2x + y - 2z = -3
x + 3y - z = 4
3x + 4y - z = 5
Rewrite the system in matrix form and solve it by Gaussian Elimination (Gauss-Jordan elimination)
2 1 -2 -3
1 3 -1 4
3 4 -1 5
R1 / 2 → R1 (divide the 1 row by 2)
1 0.5 -1 -1.5
1 3 -1 4
3 4 -1 5
R2 - 1 R1 → R2 (multiply 1 row by 1 and subtract it from 2 row); R3 - 3 R1 → R3 (multiply 1 row by 3 and subtract it from 3 row)
1 0.5 -1 -1.5
0 2.5 0 5.5
0 2.5 2 9.5
R2 / 2.5 → R2 (divide the 2 row by 2.5)
1 0.5 -1 -1.5
0 1 0 2.2
0 2.5 2 9.5
R1 - 0.5 R2 → R1 (multiply 2 row by 0.5 and subtract it from 1 row); R3 - 2.5 R2 → R3 (multiply 2 row by 2.5 and subtract it from 3 row)
1 0 -1 -2.6
0 1 0 2.2
0 0 2 4
R3 / 2 → R3 (divide the 3 row by 2)
1 0 -1 -2.6
0 1 0 2.2
0 0 1 2
R1 + 1 R3 → R1 (multiply 3 row by 1 and add it to 1 row)
1 0 0 -0.6
0 1 0 2.2
0 0 1 2
x = -0.6
y = 2.2
z = 2
Answer: The equation that represents the give situation is, y = 0.75 x + 12
Step-by-step explanation:
Here, x represents the number of batteries the child bought and y represents the total cost.
Since, the cost of one batteries = $ 0.75
⇒ The cost of x batteries = 0.75 x
The cost of one toy = $ 12
Hence, the total cost = The cost of one toy + The cost of x batteries
= y = 0.75 x + 12
Which is the required equation that represents the given situation.
Answer: b
Step-by-step explanation:
Answer:
A) y=-6x+1
Step-by-step explanation:
m=(y2-y1)/(x2-x1)
m=(-17-(-5))/(3-1)
m=(-17+5)/2
m=-12/2
m=-6
y-y1=m(x-x1)
y-(-5)=-6(x-1)
y+5=-6(x-1)
y=-6x+6-5
y=-6x+1
Arc length from A to C (red line) is the given inside angle times 2, so AC = 50*2 = 100 degrees.
A full circle is 360 degrees, so arc ABC (blue line) would be 360 - 100 = 260 degrees.
The answer is D.
