1. Solve. Check your solution. 9x - 6 = 66 2. Solve. Check your solution. 23 - 4x = 9x - 3 3. Solve the following equation and check the solution. 12(y - 1) = - 2(7 + y) 4. Solve 4/5-x/10=1 5. Solve. 6x + 15 = 3 + 8x - 6 6. Write algebraic equation for the following problem and then solve it. The population of a country in 2015 was estimated to be 321.7 million people. This was an increase of 29% from the population in 1990. What was the population of the country in 1990? 7. Write algebraic equation for the following problem and then solve it. Creekside dormitory just purchased a new clothes dryer on sale for $507. The sale price was 65% of the original price. What was the original price of the clothes dryer? 8. Write algebraic equation for the following problem and then solve it. A town's employment statistics show that 945 of its residents were unemployed last month. This is a decrease of 25% from the previous month. How many residents were unemployed in the previous month? 9. Write algebraic equation for the following problem and then solve it. In a reforestation program, 4270 seedlings were planted. Twice as many poplars as balsams were planted. The number of elms planted was 70 more than triple the number of balsams. How many of each type of seedling was planted? Let x = the number of balsam seedlings. Write equation, in terms of x, for the 4270 seedlings that were planted. 10. Write algebraic equation for the following problem and then solve it. Beth decided to invest $14,000 of her retirement fund conservatively. She invested part of this money into one account that pays 5% simple interest and part into another account that pays 4% simple interest. Last year she earned $640 in interest. How much did she invest in each type of account? Let x = the amount invested at 5% interest. Write expression that is equal to 640, the amount of interest she earned last year, using the variable x.