Zachary purchased a computer for $1,100 on a payment plan. Two months after he purchased the computer, his balance was $820. Four months after he purchased the computer, his balance was $540. What is an equation that models the balance y after x months? (Type your answer in slope-intercept form. Use integers or fractions for any numbers in the equation. Do not include the $ in your answer.)

When you answer this can you explain

Suppose that 3% of all athletes are using the endurance-enhancing hormone epo (you should be able to simply compute the percentage of all athletes that are not using epo). for our purposes, a “positive” test result is one that indicates presence of epo in an athlete’s bloodstream. the probability of a positive result, given the presence of epo is .99. the probability of a negative result, when epo is not present, is .90. what is the probability that a randomly selected athlete tests positive for epo? 0.0297

Which of the following would be a reasonable estimate for the weight of a pencil? a. 1 × 10^-20 lb b. 1 × 10^20 lb c. 1 × 10^2 lb d. 1 × 10^-2 lb