9^x + 9^x-1 = 30 what's the value of x​

What value of x is in the solution set of –5x – 15 > 10 + 20x?

For one history test, keith had to answer 40 questions. of these 40 questions, keith answered 28 of them correctly. what percent did keith get on his history test? round your answer to the nearest tenth if necessary

5(-9w) put expression in distributive property