Answer:

Step-by-step explanation:
From the question we are told that
System of equations given as
x₁ + 3x₂ + x₃ + x₄ = 3;
2x₁ - 2x₂ + x₃ + 2x₄ = 8;
x₁ - 5x₂ + x₄ = 5
Matrix form

Generally the echelon reduction is mathematically applied as

Add -2 times the 1st row to the 2nd row

Multiply the 2nd row by -1/8

Add -1 times the 2nd row to the 3rd row

Multiply the 3rd row by -8/41

Add -1/8 times the 3rd row to the 2nd row
Add -1 times the 3rd row to the 1st row

Add -3 times the 2nd row to the 1st row

3x+2y=22
3x-2y=2
we add these to equations together
6x=24
x=4
then we plug in x to find y
3*4+2y=22
12+2y=22
2y=10
y=5
solution is (4,5) (x=4 and y=5)
Answer:

Step-by-step explanation:
This is a compound inequality that basically states that the X value is greater than or equal to -5, but less than or equal to -1. It is inclusive, because it includes both numbers and therefore should have an equal to sign (
) instead of just less than or greater than ( < or >).
Answer: 15=10+5
Step-by-step explanation:
Subtract 55 from both sides.
15-5=a
Simplify 15-5 to 10.
10=a
Switch sides.
a=10