The equation of a line in slope-intercept form, is:
[tex]y=mx+b[/tex]
Where m represents the slope of the line (rate of change), and b represents the y-intercept of the line (initial value).
Since the rose grows 1.5 cm per day, then the rate of change is 1.5:
[tex]m=1.5[/tex]
Since today the rose is 5cm high, then the initial value is 5:
[tex]b=5[/tex]
Then, the height of the rose after x days is:
[tex]y=1.5x+5[/tex]
To find the height of the rose after 20 days, substitute x=20:
[tex]\begin{gathered} y=1.5(20)+5 \\ =30+5 \\ =35 \end{gathered}[/tex]
Then, the height of the rose after 20 days is 35 cm.
