Answer:
Step-by-step explanation:
A) Samantha's answer is incorrect because 15r ----> 15*r. So when 15 goes to other side, multiplication will change to division (not subtraction)
15r = 105
divide both sides by 15
[tex]\frac{15r}{15}=\frac{105}{15}\\\\r=7[/tex]
B)This equation has only one solution.