Is y = 2.5 y=2.5 a solution to the following equation? 3 − y = 6.8 + y 3-y=6.8+y

In this problem we are asked if y equals 2.5 is a solution to the following equation. Now the way I'm going to solve this is by taking every place that I see y and replacing it with 2.5. So this is going to give us 3. -2.5. On the left side And then that's going to equal 6.8 plus 2.5 on the right side. Now we need to figure out if this is in fact a true statement. So let's go ahead and start with the left side. On the left side I have 3, and I'm subtracting off 2.5. So to subtract these, I need to make sure the decimal points are aligned and remember whole numbers can be written with a decimal point after the last place that we see. So from here I can just go ahead and write this 0 to align everything and now we can subtract. Now 0 minus 5, we can't do that because 5 is greater than 0, so I need to go ahead and borrow from this 3 and make it a 2, in which case the 0 becomes 10 and we get 10 minus 5, which is 5. Now next we're going to have 2 minus 2, which is 0. I can go ahead and bring down that decimal point, giving us 0.5. So this whole left side comes out to 0.5. Now is that equal to the right side? Well, on the right side we have 6.8 plus 2.5. And let's go ahead and do this math. Now 8 + 5 gives us 13, so we have the 3, and then we carry the 1. Then we have 6 + 2 + 1, which comes up to 9. That can bring that decimal point right down. So on the right side we get 9.3. 9.3 and 0.5 are obviously not equal to each other. So because these are not equal, we can say that this y equals 2.5 is not a solution to the problem.