You have to find the area of the four triangles which is the perimeter of the base and multiply. It by your height and your case you have to find out if it’s a slant height.
M=change in y/change in x
Finding gradient of the orginal line
=3+1/0-3
=-4/3
Since parallel lines are equal the other line would be -4/3 (gradient)
Sub (-3;2) into y=mx+c
2=-4/3 (-3)+c
2=4+5
2-4=c
-2 = c
Therefore sub all your info and you get y= -4/3x-2
Invested amount (P) = $300.
Time in years (t) = 2 years.
Balance after 2 years (A) = $329.49.
Let us assume rate of interest = r % compounds annually.
We know, formula for compound interest

Plugging values in formula, we get




Taking square root on both sides, we get





r=0.048.
Converting it into percentage by multiplying by 100.
r=0.048 × 100
r = 4.8 %
Therefore, the rate of interest on the account is 4.8% compounds annually.