X-12 square root of x+36=0 what is the value of x

Describe all the numbers that when rounded to the nearest thousand are 645,000

Which statement best describes the polynomial

The party planning committee has to determine the number of tables needed for an upcoming event. if a square table can fit 8 people and a round table can fit 6 people, the equation 150 = 8x + 6y represents the number of each type of table needed for 150 people.