Question

Part AKarissa says that to represent the expression - 7 - (-9) on a number line, she should start at 7 and move 9 units to the left.Is she correct? Explain why or why notRespond in the space provided.Part BHugo thinks that the equation below is true.( 3) + ( 8) - 4 = ( 3) - 8 - 4Is he correct? Explain why or why not.Respond in the space provided

Answer 1

PART A:

In the expression -7 - (-9), we can combine both negative signals and create a positive signal, so the expression will be -7 + 9.

That means in the number line we start at the number -7 and go 9 units to the right.

So Karissa is not correct, because she said a different starting point and a different direction to add the 9 units.

PART B:

Let's solve the equation:

`\begin{gathered} (3)+(8)-4=(3)-8-4 \\ 3+8-4=3-8-4 \\ 7=-9 \end{gathered}`

We can see that the equation is not true, since the final statement is false. So Hugo is not correct, because the final values of each side of the equation didn't match.