Solve for a: -2(4a+8)=24

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  1. -2(4a+8)=24

    -8a - 16 = 24
    -8a = 24 + 16
    -8a = 40
    a = -5

  2. I know these types of problems are a little confusing at first but once you get the system down you probably won't have any trouble.
    To find out what a equals you will need to do some elimination, right? Just like trying to find out who stole a cookie you will need to eliminate suspects.
    Now here is the problem.

    Use reasoning to see what the equation says. This equation says that -2x4a,
    and -2x8 will tell you what a is if you talk to 24 in algebraese.
    What is -2x4a? -8a
    How about -2x8, -16
    remember when you multiply any number by a negative number it will be negative.
    So now -8a and -16 have to talk to 24.
    So, who has to talk first? -16. Why? Because you are trying to find a and to do that you have to get -16 out of the way.
    So to do that you move him over to 24 to talk.
    Now you have -8a-16=24
    To move -16 you have to make sure he's actually there. To do that you have to eliminate -16 from the left side. Who actually goes over to talk to someone and is in two places at the same time? To make sure -16 is not in two places at the same time the negative sign has to be removed.
    what is 24+16? 40
    Now we are starting to see who a is.
    How do we narrow our suspect? We eliminate our last one, -8 However, we can't shove -8 over to talk to 40.
    So we divide both sides by 8. Then the only thing left is a.
    I will let you do that. You actually can see who a is by looking at it now.

    Here it is step by step.
    -2x4a=-8a and -2x8=-16
    1a=5 remember a variable with 1 is the variable.
    1a=a, so

    Does this make sense?

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