Having rewritten the equation in standard form, we can enter it in the calculator by pushing Y= and typing it in the first row.
Next, by pushing 2ND and GRAPH, we get a table of values for whole number inputs of x. We are looking for x-values that make the y-column equal 0.
From the table, we can see that the y-values change signs from positive to negative. Thus, y must reach 0 when x is somewhere between - 1 and 0. To find the exact value, we will need to view smaller increments in the table. To change the table settings, push 2ND and WINDOW. Then change the TblStart to - 1 and △ Tbl to 0.01.
Now push 2ND and GRAPH to see the table again with the new configurations.
As we can see, 0 is still not showing in the y-column. However, now we can estimate the x-value more accurately. Notice that 0.0382 and - 0.0032 are the closest to 0. Since - 0.0032 is closer, we can estimate the first solution of our equation to be - 0.78.
x≈- 0.78
To find the second solution return to the original display and identify the other change in sign of y-values. Then, follow the same process as before.
We can estimate the second solution to be 1.28.
x≈ 1.28
