Percy is plotting points on a graph. the ratio of y-value to x-value is 2 to 3 for each point. what will be the x-value of a point with a y-value of 18?

You have $600,000 saved for retirement. your account earns 5.5% interest. how much, to the nearest dollar, will you be able to pull out each month, if you want to be able to take withdrawals for 20 years?

Each person in an it department of 25 people works on at least one of 3 major projects: system security, program implementation, platform development. 10 people work on system security, 13 work on program implementation, and 12 work on platform development. 4 people work on system security and platform development, 5 people work on program implementation and platform development, and 2 people work on all three projects. how many people work on system security and program implementation?

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.