Answer:
11.20
Step-by-step explanation:
Multiply both equations by 100:
19.99=1999
8.79=879
1999-879=1120
Divide by 100:
1120/100=11.20 saved ................
No, it is an imaginary number.
Can't take the square root of a negative number without creating a method termed an imaginary number, which is the square root of -1 which they have used " i " to signify.
Then square root of -11.2 would be written Sqrt(11.2)i. The Sqrt(11.2) = 3.3466
so the answer is 3.3466i