Answer
a) No
b) between $-3$ and $-1$
c) $x\le-3$
Work Step by Step
a) No, the spreadsheet does not show the solution of the equation since there is no value of $x$ for which the value in column B is equal to the value in column C.
b) The solution to the equation is between the $x$ values of $-3$ and $-1$. This is because when the $x$-value is less than or equal to $-3$ the value in column B is less than the value in column C. But when the $x$-value is greater than or equal to $-1$, the value in column B now becomes greater than the value in column C. This means that somewhere between the $x$-values of $-3$ and $-1$, the value of column B became equal to the value in column C.
c) Examining the values in column B and column C, then $7(x+1)$ is less than $3(x-1)$ when $x\le-3$.
