You are here:

# Algebra/Algebra/ Matrix

Question
Can you explain to me how to solve these matrix equation? These two are throwing me off.

5x - [1.5 -3.6]   [0.2  1.3]
[-0.3 2.8] = [-5.6 1.7]

-3y + 2[6    9]   [27 -18]
[-12 15] = [30   6]

It looks like the equations have 2x2 matrixes, so x and y are also 2x2 matrices.

1.5 -3.6
-0.3  2.8
to both sides gives
1.5+0.2  -3.6+1.3
-0.3-5.6   2.9+1.7
on the right side.

The result of this is
1.7 -2.3
-5.9  4.5.

Since this is 5x, dividing by 5 gives
0.34 -0.46
-1.18  0.9.

This is the matrix solution for x.

For y, multiply the matrix by 2 giving
12 18
-24 30.

Subtracting this from both sides gives
15 -36
42  -9.

Since this is -3y, divide the entire matrix by -3 and get
-5 12
-14  3.

This is the y matrix.

Questioner's Rating
 Rating(1-10) Knowledgeability = 10 Clarity of Response = 10 Politeness = 10 Comment Thank you so much on helping me understand how to solve matrcies like those. I really get it now. I made a 100 on my test yesterday. Again, thank you so much.

• View Follow-Ups

Algebra

Volunteer

#### Scott A Wilson

##### Expertise

Any algebraic question you've got. That includes question that are linear, quadratic, exponential, etc.

##### Experience

I have solved story problems, linear equations, parabolic equations. I have also solved some 3rd order equations and equations with multiple variables.

Publications
Documents at Boeing in assistance on the manufacturiing floor.

Education/Credentials
MS at math OSU in mathematics at OSU, 1986. BS at OSU in mathematical sciences (math, statistics, computer science), 1984.

Awards and Honors
Both my BS and MS degrees were given with honors.

Past/Present Clients
Students in a wide variety of areas since the 80's; over 1,000 of them have been in algebra.