We have the expression
[tex]5x+2x[/tex]We have to convert the expression in a single-term expression. We apply the distributive property:
[tex]5x+2x=(5+2)\cdot x=7x[/tex]b) We have to substitute five different values into the expressions 5x+2x and 7x-1.
The first expression is equal to 5x+2x=7x.
We then can predict that the difference between 7x and 7x-1 is 1.
For example, for x=2, we have 7x=7*2=14 and 7x-1=7*2-1=14-1=13.
We can calculate if the two expressions can be equal, we write:
[tex]\begin{gathered} 5x+2x=7x=7x-1 \\ 7x=7x-1 \\ 7x-7x=-1 \\ 0=-1\longrightarrow\text{False} \end{gathered}[/tex]There is no value that can make both expressions equal.
Both equations have a difference of 1 for any value of x.