Saturday

March 28, 2015

March 28, 2015

Posted by **ann** on Thursday, July 26, 2007 at 10:25pm.

should i use substitution or add them?

"First" + 3 times "Second" eliminates y:

x + 3y + 3*(3x - y) = 5 + 3*5 --->

10 x = 20 ---->

x = 2

Inserting in "First" gives:

2 + 3 y = 5 --->

3 y = 3 ---->

y = 1

This problem is a bit too easy to practice solving equations. You should try to practice yourself by giving three variables x1, x2, x3 arbitrary values, say

x1 = 4, x2= 13, x3 = 3

and then evaluate three different linear functions of the x1, x2 and x3, e.g.

x1 + 2 x2 - 7 x3 = 9

2 x1 - x2 + x3 = 6

-x1 + 5 x2 - 3 x3 = 52

Then try to solve these three equations. If you do it correctly you should obtain the values you used for x1 x2 and x3 for the solution. It can happen, though, that you find more solutions than the values you started out with.

**Answer this Question**

**Related Questions**

algebra2 - solve the systems of equation: First : 4x-2y = 2 Second: y = -4x-7 ...

Alg-Substitution (check plz) - k well i had to use substitution to find the ...

Algebra 1 - What is an equation of a line perpendicular to the line with ...

Math - The sum of two numbers is 112. The second is 7 more than 4 times the ...

algebra - I have been working this one for awhile and have become more confused...

Math - I need help,my example: The sales representative say there are two floor ...

subsitution method - Can some one show me how to use the Substitution method to ...

Substitution Method-Plz help - Use the Substitution method to solve the system ...

Algebra - Find two consecutive positive integers such that the sum of the square...

science - A stone is dropped into a river from a bridge 43.9 m above the water...