Civil Engineering Reference
In-Depth Information
Next, Equation 2.2b is subtracted from 2.1b and becomes 2.3a. Equation
2.2c is subtracted from 2.1c and becomes 2.3b. Equation 2.2a now
becomes 2.3c, thereby moving to the bottom.
5
x
−=
7
(2.3a)
2
3
9
2
19
2
2
x
− −
(2.3b)
2
3
5
2
13
2
xx
−+ =
x
(2.3c)
1
2
3
Now, Equation 2.3a is divided by the first unknown in that equation, 5,
and the new Equation 2.4a is multiplied by the corresponding coefficient
of that unknown from the two other equations (2.3b and 2.3c) to yield
Equations 2.4b and 2.4c.
1
5
7
5
x
−=
x
(2.4a)
2
3
2
5
14
5
2
x
−=
(2.4b)
2
3
1
5
7
5
−+ =−
x
x
(2.4c)
2
3
Just as the previous cycle, Equation 2.4b is subtracted from 2.3b and
becomes 2.5a. Equation 2.4c is subtracted from 2.3c and becomes 2.5b.
Equation 2.4a now becomes 2.5c.
41
10
123
10
−
x
= −
(2.5a)
23
10
79
10
x
+
x
=
(2.5b)
1
3
1
5
7
5
x
−=
x
(2.5c)
2
3
