Good morning, and Happy Monday! Today's Math Monday blog assignment is to explain the steps we would use to find the answer to the equation 2x - 7 = 15.
- The first step you'd carry out to do the problem, if you were to do it on paper, would be to draw a line down the equals sign, just for the sake of organization. This makes it easier for us to keep track cognitively of what we've done.
- Next you would look at the left-hand side of the problem. You would find out what operation is involved between 2x and the constant 7. You'd do the inverse of this operation -- since the equation says to subtract 7, we'd do the opposite and add 7. Cross out the 7, we don't need it.
- Now we do the same thing to the other side. Add 7 to 15. This makes 22. Our equation now says 2x = 22.
- Do another inverse operation. Divide both sides by the constant 2. Our first digit's value is canceled out, so now our problem reads x = 22/2.
- Do as the problem says. Divide by 22 by 2. You'll get 11. x = 11!
- You can also check your work by plugging in the variable to the equation. 2(11) - 7 = 15 --> 22 - 7 = 15. This is a valid equation.
By learning how to use inverse operations and dividing our equations into parts that correspond with each other, we simplify algebraic expressions. We learned how to do this at the beginning of the year, and it's one of the most memorable things I've learned in my math class this
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