You can determine if the answer is positive or negative because the even numbers are positive and the odd numbers are negative
A line adds up to equal 180 degrees. And adjacent angles also add to equal 180 since they share a side on a line. So add them together and make them equal 180
9x - 7 + 8.5x + 4 = 180
17.5x - 3 = 180
17.5x = 183
x = 10.5
First. You have to look at what kind of proportionality it is.It is an Inverse Proportion.so you see the rate of change is 2.3
