Directions: Simplify the following monomials (if possible). 12.) 12b + 8a - 10b
13.) 13y² + 9y + 4y² - 31y
14.) 10m²n + 7mn² - m²n
15.) Find the sum of 16y² and -5y²
16.) Find the difference of 10x²y and 2x²y

-ANYONE PLEASE HELP ME I REALLY NEED THE ANSWER RIGHT NOW BECAUSE I HAVE TO PASS THIS LATER AND THE DEADLINE IS TODAY I HOPE Y'ALL CAN HELP ME:(
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James is playing his favorite game at the arcade. after playing the game 3 times, he has 8 tokens remaining. he initially had 20 tokens, and the game costs the same number of tokens each time. the number tt of tokens james has is a function of gg, the number of games he plays

The rate of decay of a radioactive substance depends upon the amount present initially. the mass y (mg) of the radioactive substance cobalt-60 present in a sample at time t (years) is represented by the exponential equation y=50e −0.1315 t . answer the following questions in complete sentences. 1. how does the exponential equation above compare to the equation for simple interest that is compounded continuously? explain the similarities. 2. what is the initial amount of cobalt-60 in the sample? 2. how much cobalt-60 is left after 8.4 years? show your work. 3. what would be the y-intercept of the graph? what does it represent? 4. after how many years will the amount of cobalt-60 left be 6.25 mg? explain what happens to the cobalt-60 after 50 years? 5. discuss some “real-world” examples and uses of cobalt-60

Solve the equation -9p - 17 =10 a -3 b. 16 c. 18 d -16