Monday

December 22, 2014

December 22, 2014

Posted by **harry** on Saturday, December 6, 2008 at 6:18pm.

2 1

-3 4

Find

2x+y=2

-3x+4y=1

- math -
**harry**, Saturday, December 6, 2008 at 6:20pmIt is supposed to be a matrix.

2, 1

-3, 4

but i donot know how to put the brackets. i used commas to seperate the numbers

- math -
**Damon**, Saturday, December 6, 2008 at 7:26pmwell, I will use gauss jordan, see the link I gave you.

2,1,1,0

-3,4,0,1

+1, .5 , .5, 0

-3, 4. , 0 , 1

multiply top by +3 and add to bottom

+1, .5 , .5 , 0

0 , 5.5, 1.5, 1

divide second row by 5.5

+1, .5 , .5 , 0

0 ,1.0, .273,.182

subtract half the second row from the first to get a new first

+1 , 0 , .364, -.091

0 , 1.0, .273, .182

so I think the inverse is

.364 , -.091

.273 , .182

multiply that by

2

1

and get

x = 2*.364 - 1* .091 = .637

y = 2*.273 +1 * .182 = .728

check

2*.637 + .728 = close enough to 2

-3*.637 + 4*.728 = close enough to 1

- Took me a while -
**Damon**, Saturday, December 6, 2008 at 7:28pmI have not inverted a matrix by hand for a while :)

- Took me a while -

**Answer this Question**

**Related Questions**

inverse - find f^-1 (x). (this is asking me to find the inverse) f(x) = -(x-2)^2...

algebra - 1 (a) A function passes through the points (0, -5), (1, 0), (2, 7). ...

math - The cost of producing q articles is given by the function C=f(q)=100+2q...

Math - Determine whether each equation is true for all x for which both sides of...

Inverse of log function - Find the inverse of f(x) = log(2+x) - 4 the base is "a...

math - how do you find the equations inverse and the domain of the inverse f(x...

inverse - If f(x)=cosx + 3 how do I find f inverse(1)? Thanks y = cos(x) + 3 the...

math - using the inverse property of division how would you isolate -4.2? ...

math - Could you show me step by step how to find the inverse of this problem: ...

Algebra II (Matrices) - My book doesn't solve it like a linear equation, they ...