I'd say option b, you can learn why by isolating x.
Answer:
{x,y,z}={1,3,4}
Step-by-step explanation:
System of Linear Equations given :
[1] x + 3y - 2z = 2
[2] 3x + 2y + z = 13
[3] -2x + 3y - 3z = -5
Solve by Substitution :
// Solve equation [2] for the variable z
[2] z = -3x - 2y + 13
// Plug this in for variable z in equation [1]
[1] x + 3y - 2•(-3x-2y+13) = 2
[1] 7x + 7y = 28
// Plug this in for variable z in equation [3]
[3] -2x + 3y - 3•(-3x-2y+13) = -5
[3] 7x + 9y = 34
// Solve equation [3] for the variable y
[3] 9y = -7x + 34
[3] y = -7x/9 + 34/9
// Plug this in for variable y in equation [1]
[1] 7x + 7•(-7x/9+34/9) = 28
[1] 14x/9 = 14/9
[1] 14x = 14
// Solve equation [1] for the variable x
[1] 14x = 14
[1] x = 1
// By now we know this much :
x = 1
y = -7x/9+34/9
z = -3x-2y+13
// Use the x value to solve for y
y = -(7/9)(1)+34/9 = 3
// Use the x and y values to solve for z
z = -3(1)-2(3)+13 = 4
Solution :
{x,y,z} = {1,3,4}
The answer is 7418.
Hope this helps
30
Step-by-step explanation:
It will take her 51.4 minutes.
Explanation:
You would do 12/7 and then multiply that answer by 30.
