In the equations of law of cosines do i multiply the two by both a and b or just a?

Brook states that the distance on the line is 4 units. caleb states that the whole line does not have a distance because it continues on forever. vivian states that the line is 6 units long. which distance did brook measure? which distance did vivian measure?

The weight of an object in the water is 7% of its weight out of the water. what is the weight of a 652g object in the water?

The square root of 9x plus 7 plus the square rot of 2x equall to 7