When two matrices are equal, every element in the same position must be equal.
[2x+105xy2+1]=[x+301026]
Matching each position gives the following equations:
Top-left: 2x+1=x+3
Top-right: 5x=10
Bottom-left: 0=0 (always true)
Bottom-right: y2+1=26
From the top-right equation:
5x=10
x=510
x=2
From the bottom-right equation:
y2+1=26
y2=25
y=±5
So y=5 or y=−5
Since x=2 and y can be 5 or −5:
When y=5:
x+y=2+5=7
When y=−5:
x+y=2+(−5)=−3
Therefore, the possible values of x+y are 7 and −3.