A6 feet tall boy cast a shadow of 9 feet at the same time of the day if the shadow of a tree measures 21 feet what is the height of the tree

In the diagram, the measure of angle 9 is 85° which angle must also measure 85°?

Match the equivalent expressions. x - 3y + 12 12 - 3y - 2x + x + 2x 3x + 2y - 2x + y + 12 3y + 12 3x + y - 12 4y + 3y + 3x - 6y - 10 - 2 x + 3y + 2x - 3x + 7 + 5 x + 3y + 12 5 + 2y + 7x - 4x + 3y - 17

James adds two numbers a + b. sally adds the same two numbers but reverse the order b + a what property of addition assures us that james and sally will get the same sum