The square of a number decreased by 15 is equal to twice the number. find the number

Rearrange the formula c^2 = a^2 + b^2 for b

Ablock of wood is a cube whose side is x in. long. you cut off a 1-inch thick piece from the entire right side. then you cut off a 3-inch thick piece from the entire top of the remaining shape. the volume of the remaining block is 2,002 in3. what are the dimensions of the original block of wood?

Write two subtraction equations that are equivalent to 5 + 12 = 17.