Final Answer:
The linear approximation for √(64.4) using the tangent line at
is approximately

Step-by-step explanation:
To find the linear approximation, we first need to compute the slope m and the y-intercept b for the tangent line at

The slope
is the derivative of
evaluated at

The y-intercept
where
.
Hence, the equation of the tangent line is
.
To approximate √(64.4), we plug in
into the equation of the tangent line:
![\[y ≈ (1/16) * 64.4 + 4\]](https://img.qammunity.org/2024/formulas/mathematics/high-school/irfepj51sdk0ahnodzi9nnync9s95zbe3g.png)
![\[y ≈ 4.025 + 4\]](https://img.qammunity.org/2024/formulas/mathematics/high-school/yw9omqa1qr2hxegl7n7i2sub09fx452j19.png)
![\[y ≈ 8.025\]](https://img.qammunity.org/2024/formulas/mathematics/high-school/rnav4k8q3gkg99roaeha75bzbk40vs3sc3.png)
Therefore, the linear approximation for √(64.4) is approximately
. This method is a useful approximation when dealing with small changes in a function and provides a close estimate without the need for complex calculations.