You are here:

Advanced Math/When using Cramer's Rule to...

Advertisement

Expert: Sherman D. - 7/12/2005


Question
When using Cramer's Rule to solve the system of equations
containing 5x-y=5, -3x+y=-9 the denominator for the x and y
variables look like what determinant?

Answer
5x - y = 5
-3x + y = -9

|5,-1|
|-3,1|

D = ad - bc

D = (5 * 1) - (-1 * -3)
D = 5 - 3
D = 2

x =
|5,-1|
|-9,1|
------
2
x = (5 - 9)/2, (-4/2) = -2

y =
|5,5|
|-3,-9|
-------
2

y =  (-45 - (-15))/2, (-30)/2, -15

so

x = -2
y = -15

Info found at http://mathworld.wolfram.com/CramersRule.html

Not certain what you mean by "look like what determinant"

But i can tell you 5 - 3 = The determinant

Other than that, you can derive your answer from what i have shown you.

Advanced Math

All Answers

Answers by Expert:

Ask Experts

Volunteer

Sherman D.

Expertise

I can answer questions dealing in mathematics of all kinds except for Physics and Calculus, but i can answer questions in Pre-Calculus and Chemistry. I can also answer questions in Recipes of all kinds. I can find games cheats/walkthroughs, but i can`t find a specific game online or offline. I can also do history and recipes for alcoholic beverages.

Experience

Mathematics, Recipes, History, and Games.

Education/Credentials
High School graduated. I graduated with honors, and i was in Beta Club for a year and a half.

Awards and Honors
Principle's list and A and B honor roll in high school only.

©2012 About.com, a part of The New York Times Company. All rights reserved.