SOLUTION: Find all X and Y (in R) so that A*A=A*B A=[ X, 0 -3, Y] B=[2, 0 4, Y] I've tried this: A*A=[X^2, 0 -3X-3Y, Y^2] A*B=[2X, 0 -6+4Y, Y^2] X^2

Algebra ->  Matrices-and-determiminant -> SOLUTION: Find all X and Y (in R) so that A*A=A*B A=[ X, 0 -3, Y] B=[2, 0 4, Y] I've tried this: A*A=[X^2, 0 -3X-3Y, Y^2] A*B=[2X, 0 -6+4Y, Y^2] X^2      Log On


   

Question 994579: Find all X and Y (in R) so that A*A=A*B
A=[ X, 0
-3, Y]
B=[2, 0
4, Y]
I've tried this:
A*A=[X^2, 0
-3X-3Y, Y^2]
A*B=[2X, 0
-6+4Y, Y^2]
X^2=2X
X^2-2X=0
X*(X-2)=0
X1=0 X2=2
-3X-3Y=-6+4Y
6=7Y
Y1=6/7
Y2=0
Is my solution correct? Thank you!
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Yes, (X,Y)=(0,6/7) and (X,Y)=(2,0) are correct.
Well done.