3a - 12b = 9
14a - 11b = 5
To eliminate a. The LCM of 3 and 14 is 42.
Multiply the first equation thru by 14,
and the second equation by -3
14[ 3a - 12b = 9]
-3[14a - 11b = 5]
42a - 168b = 126
-42a + 33b = -15
-------------------
-135b = 111
b = 111/(-135)
b = -37/45
Since -37/45 will be hard to substitute into
one of the equations, we start over and
eliminate b:
The LCM of 12 and 11 is 132.
Multiply the first equation thru by 11,
and the second equation by -12
11[ 3a - 12b = 9]
-12[14a - 11b = 5]
33a - 132b = 99
-168a + 132b = -60
-------------------
-135a = 39
a = 39/(-135)
a = -13/45
a = -13/45 b = -37/45
(a, b) = (-13/45, -37/45)
Edwin
AnlytcPhil@aol.com
