Letter b. (2,5) is the only one that when plugged into the inequality above still makes the inequality true because 7<=7 and 5>2
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}
Let the solutions be a and b.
a = -2; b = -10
a + b = -2 + (-10) = -12
ab = (-2)(-10) = 20
(x - a)(x - b) = 0
(x - (-2))(x - (-10)) = 0
(x + 2)(x + 10) = 0
x^2 + 10x + 2x + 20 = 0
x^2 + 12x + 20 = 0
-h = 12
h = -12
4k = 20
k = 5
Answer: the answer is 8
Step-by-step explanation:
Answer:
Step-by-step explanation:
$2400 in labor
