What is the sum of x2-3x+7 and 3x2+5x-9

While scuba diving, rajeev dove to a depth of 12.6 feet below the surface of the water and then descended another 8.7 feet. what expression can be used to find rajeev's new position? 12.6 – 8.7 –12.6 – 8.7 –12.6 – (–8.7) 12.6 – (–8.7)

Write numerical coefficient of y² in the expression 2x² - 15xy – 7y²

8000 + 8800 + 8000 + 8 million + 80 trillion + another a katrillion equals