Why is the gcf of two numbers sometimes 1

What is the nth term rule of the linear sequence below? 27 , 25 , 23 , 21 , 19 , . .

Match each equation with the operation you can use to solve for the variable. 1 subtract 10 2 divide by 10 3add 18 4add 10 5 subtact 18 6multiply by 5. 7multiply by 10. a 5 = 10p b p + 10 = 18 c p + 18 = 5 d 5p = 10

Which rational number could be graphed between -4 and -5