What is the value of x for the polygon shown below

Find the rate of change for the situation.you run 7 miles in one hour and 21 miles in three hours.

Asap! will mark brainliest! ( respond asap, it's urgent! : )) what is the slope for equation y =-3x + 8

Dylan is evaluation the expression 13+19+7+10 at one step in his work, dylan rewrites the equation as 13+7+19+10 which property of addition must dylan have used when he evaluated the expression?