Multiply both sides of the second equation by 4. That will give you -4x in the second equation which when added to 4x of the first equation will eliminate x.
Second equation:
-x + 3y = 6
Multiply the second equation by 4 on both sides:
-4x + 12y = 26
Hey,
Fractions can be decomposed in many different ways. Decomposing a fraction means breaking it up into smaller parts.
For example you can write 3/5 as 1/5+1/5+1/5 or as 1/5+2/5.
4a + 6b = 10
2a - 4b = 12...multiply by -2
----------------
4a + 6b = 10
-4a + 8b = - 24 (result of multiplying by -2)
------------------add
14b = - 14
b = -14/14
b = -1
2a - 4b = 12
2a - 4(-1) = 12
2a + 4 = 12
2a = 12 - 4
2a = 8
a = 8/2
a = 4
so 12a = 12(4) = 48 <==
