Evaluate ab÷cd for a=5 b=-2 c=4 and d=-65/12-5/12-3/23/2

Abox contains 1 plain pencil and 4 pens. a second box contains 5 color pencils and 5 crayons. one item from each box is chosen at random. what is the probability that a plain pencil from the first box and a color pencil from the second box are selected? write your answer as a fraction in simplest form.

Find the center and the radius of the circle with the equation: x^2-2x+y^2+4y+1=0?

Solving algebraic equations 2m+3=11