Twice a number decreased by eight is zero

Discussion in 'Calculator Requests' started by math_celebrity, Jan 20, 2024.

  1. math_celebrity

    math_celebrity Administrator Staff Member

    The phrase a number means an arbitrary variable. We can pick any letter a-z except for i and e.

    Let's choose x.

    Twice a number:

    decreased by eight
    2x - 8

    is means equal to. Set 2x - 8 equal to zero for our algebraic expression:
    2x - 8 = 0

    If the problem asks you to solve for x, add 8 to each side:
    2x = 8

    Divide each side by 2:
    x= 4

Share This Page