Posted by **Anon** on Monday, April 1, 2013 at 5:44pm.

3a + 5b = 70

6a + 9b = 135

- Algebra 8th grade -
**Henry**, Wednesday, April 3, 2013 at 3:08pm
Multiply both sides of the 1st Eq by -6.

Multiply both sides of the 2nd Eq by 3.

Then add the Eqs.

-18a - 30b = -420

+18a + 27b = 405

-3b = -15

b = 5.

in the 1st Eq, replace b by 5:

3a + 5*5 = 70

3a = 70-25 = 45

a = 15

- Algebra 8th grade -
**han**, Thursday, November 6, 2014 at 6:01am
62ab

- Algebra 8th grade -
**Anonymous**, Tuesday, October 27, 2015 at 6:03pm
lkmholjyul;ukyuj7y6gr48u565479

+7+45236352478

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