Step-by-step explanation:
2x - 3y - 2z = 4
[2] x + 3y + 2z = -7
[3] -4x - 4y - 2z = 10
Solve by Substitution :
// Solve equation [2] for the variable x
[2] x = -3y - 2z - 7
// Plug this in for variable x in equation [1]
[1] 2•(-3y-2z-7) - 3y - 2z = 4
[1] - 9y - 6z = 18
// Plug this in for variable x in equation [3]
[3] -4•(-3y-2z-7) - 4y - 2z = 10
[3] 8y + 6z = -18
// Solve equation [3] for the variable z
[3] 6z = -8y - 18
[3] z = -4y/3 - 3
// Plug this in for variable z in equation [1]
[1] - 9y - 6•(-4y/3-3) = 18
[1] - y = 0
// Solve equation [1] for the variable y
[1] y = 0
// By now we know this much :
x = -3y-2z-7
y = 0
z = -4y/3-3
// Use the y value to solve for z
z = -(4/3)(0)-3 = -3
// Use the y and z values to solve for x
x = -3(0)-2(-3)-7 = -1
Solution :
{x,y,z} = {-1,0,-3}
What is 7x30 = 7 x --- tens = --- tens = ---
The total area is given by:
A1 = (300) * (500)
A1 = 150000 feet ^ 2
The area occupied by 5 people is:
A2 = (5) * (5)
A2 = 25 feet ^ 2
Then, we can make the following rule of three:
5 --------> 25
x --------> 150000
Clearing x we have:
x = (150000/25) * (5)
x = 30000
Answer:
D. 30,000 people
