Question Video: Solving One-Step Linear Addition Equations in Real-World Contexts Mathematics • 6th Grade

Video Transcript

In 2016, Mississippi and Georgia had a total of 21 electoral votes. If Mississippi had six electoral votes, solve the equation six plus 𝑔 equals 21 to find the number of electoral votes that Georgia had 𝑔.

Here, we’ve actually been given an equation: six plus 𝑔 equals 21. And our goal is to solve for 𝑔. To solve for 𝑔, we want to get the 𝑔 by itself. We want to isolate this 𝑔 variable. To do that, we’ll need the inverse property of addition, which tells us that any value if you add its opposite equal zero. To get 𝑔 by itself, we want to get rid of the six. And we can do that by subtracting six. Six minus six equals zero. But we also know that to keep both sides of this equation equal, if we subtract six from one side, we must subtract six from the other side. On the left, it would be zero plus 𝑔. Or we can write that simply as 𝑔. And on the right, 21 minus six equals 15. And so, we found that 𝑔 equals 15. It’s worth checking to make sure that that’s true. Is six plus 15 equal to 21? Yes, it is. This tells us that 𝑔 is in fact 15. So, Georgia had 15 votes and Mississippi had six votes.