X+y=11
22x+15y=228
y=11-x
22x+15y=228
22x+15(11-x)=228
22x+165-15x=228
7x+165=228
7x=63
x=9
9+y=11
y=2
The solution to the system of equations is (9,2)
Do you mean 'nine and eighty four hundredths' in standard form? If so, it will be:
9.84
Y=4 (6^x)
comment if you want me to explain it