-10x-1 = 11 -9x
+10x +10x
-1 = 11 + x
-11 -11
-12 = x
x= -12
So the equation for a trapezoid is

, with the b variable being the 2 bases, h variable for height, and the a variable for area. Firstly, we will need to plug in the appropriate numbers into the equation, and it'll look like this:

Next, we will need to combine 12 and 14, then divide the sum by 2. Your equation should look like this:

Lastly, just divide each side by 13, and your answer should be
For interest rate question I=p times r times t
17=500 times r times 2
17 divide 1000
then multiply 100 to get percentage
1.7%