Step-by-step explanation:
Given
Function is [tex]y=0.18x+0.15[/tex]
where,
[tex]y=\text{Percent of the battery remaining}\\x=\text{time in hours}[/tex]
Comparing the given function with the standard slope-intercept form of the equation [tex]y=mx+c[/tex]
Here, before plugging into the laptop, the percentage of battery is
[tex]y=0.18\times 0+0.15\\y=0.15\ \text{or}\ 15\%[/tex]
The slope of the given function is [tex]0.18[/tex] i.e. in one hour it charges 18% of battery.
