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
Whats the problem? just substitute. For example: 3x-5 if x=4 so what you do is this; 3(4)-5=7
3.2-5.7=-2.5 so its have to be a negative because a smaller number subtract a bigger number have to be equal to a negative number.
Answer:
the answer is 9
Step-by-step explanation:
Answer:
<em>The slope is:</em>
Step-by-step explanation:
The slope m of a line is calculated using the following formula
Where the points 
and 
are two points belonging to the straight line
Notice in the graph that the line passes through the points
(0, 2) and (2, -1)
Then the slope is:
