Answer:
r=3.25
Step-by-step explanation:
You need to find the total distance and the total time. The total distance is two times the distance to school, 2d.s=d/t=>t=d/sWhere s is speed, d is distance and t is time. So the time taken to get to school is:d/s1and the time taken to get back is:d/s2so the total time is:d/s1+d/s2=d(1/s1+1/s2)So, as speed = distance/time, divide the total distance by the total time:2d/d(1/s1+1/s2)=2/(1/s1+1/s2)=2/(1/20+1/40)=80/3≈26.7km/hr
Answer:
B) 40/5
Step-by-step explanation:
None of these couples are solutions, (11, 3)(11, 3); (−1, −6)(−1, −6); (−3, 3)(−3, 3); <span>(7, 0). Perhaps the choice of answer are insufficient. we can add (1, 48) the couple (7, 0) and (7, 0)(1, 48) is a true answer, why? because it verifies the equation.</span>