Answer:
r = 1
Step-by-step explanation:
slope = change in y / change in x, so:
change in y / change in x = 2/3
5 - r / 7 - 1 = 2/3
5 - r / 6 = 2/3
[tex]\frac{5-r}{6}=\frac{2}{3}[/tex]
now solve this equation.
first, multiply both sides by 6 to get rid of the fraction:
[tex]5 - r = 4[/tex]
subtract 5 from both sides
[tex]-r=-1[/tex]
multiply both sides by -1
[tex]r=1[/tex]
