Answer:
5.86
Step-by-step explanation: its right on delta math
The 2 equations are
18.20x+19.50y=230.10
and
x+y=12
where x is the months of original cost and y is months for new cost. Since you know that you paid for one year (12 months) you can make the second equation. Then you want to substitute the first equations x by making the second equation
x=(12-y)
18.20(12-y)+19.50y=230.10
218.40-18.20y+19.50y=230.10
1.30y=11.70
y=9
so that means you had the original rate for 3 months and the new one for 9 months
Answer:
A(r)=15-3r
Step-by-step explanation:
switch the sign of +3r to make it -3r
For
, we have
and so
which is, again, only valid for
.
