Sunday

March 29, 2015

March 29, 2015

Posted by **Alex** on Saturday, January 30, 2010 at 1:49pm.

7x+8y=25

9x+10Y=35

- math -
**Damon**, Saturday, January 30, 2010 at 4:05pm7x+8y=25 times 5 is 35 x + 40 y = 125

9x+10y=35 times 4 is 36 x + 40 y = 140

++++++++++++++++++++++now subtract

-1 x + 0 = -15

so

x = 15

then

7(15) + 8 y = 25

105 + 8 y = 25

8 y = -80

y = -10

- math -
**Alex**, Saturday, January 30, 2010 at 4:22pmthanks but y\why did you multiply it by 4 and 5 at the begging

- math -
**Damon**, Saturday, January 30, 2010 at 6:19pmBecause 40 is the least common multiple of 8 and 10

I could have used the first times 9 and the second times 7 and eliminated x.

- math -
**Anonymous**, Wednesday, April 13, 2011 at 4:28amWhat method is this (like is it elimination,substiution)

**Answer this Question**

**Related Questions**

algebra PLZ HELP!!! - y= 9/11x-17 9x-10y=179 You need to use parentheses to tell...

math help - 5x+10y +15z-15x+10y-5z+5x-10y-5z / (5x+10y+15z)-(15x+10y-5z)+(5x-10y...

math,help - can someone help me with this i am lost now i've been doing math for...

algebra - Did I do this problem right? (2y+5w+6)(5y+5w-4) 2y(5y)+ 2y(5w) + 2y(-4...

math - how do u solve this problem -2x+7y=6 2x+10y=-6

Basic Math - I need help adding fractions with different denominators. Here is ...

math - What strategy did you use in solving this problem? 22. Suppose that you ...

English - 1. I couldn't do the shopping by myself. 2. I couldn't enjoy shopping ...

Algenra - How do I work this problem, it is not a homework problem but a problem...

Algebra - How do I work this problem, it is not a homework problem but a problem...