Question

career math i unit 5 test linear functions and equations (a
babies usually follow a straight line of increasing body length as the grow.
write the equation for the example above.

Explanation:

Step1: Identify two - point form variables

Let's take two points from the line. Say $(x_1,y_1)=(0,20)$ and $(x_2,y_2)=(4,21)$. The slope $m$ of a line is given by the formula $m=\frac{y_2 - y_1}{x_2 - x_1}$.
$m=\frac{21 - 20}{4-0}=\frac{1}{4}$

Step2: Use the slope - intercept form

The slope - intercept form of a line is $y = mx + b$, where $m$ is the slope and $b$ is the y - intercept. When $x = 0$, $y=b$. From the graph, when $x = 0$, $y = 20$, so $b = 20$.
The equation of the line is $y=\frac{1}{4}x+20$.

Answer:

$y=\frac{1}{4}x + 20$