Answer:
Step-by-step explanation:
1/7+1/13=1/t
multiply both sides by 7*13*t
13t+7t=7*13
21t=91
t=91/19
it will take 4 hours and 8 minutes
Answer:
13 I think if i´m right please mark me brainliest please thank you and have a great day
Step-by-step explanation:
Answer:
12t -3 = 18t
Step-by-step explanation:
Let
d = your friends distance in miles
t = time in hrs
Your equation:
d - 3 = 18t (1)
Because you are 3 miles behind your friend
Your Friend's equation:
d = 12t (2)
To find the amount of time t it takes for you to catch up with your friend,
Substitute (2) into (1)
d - 3 = 18t
12t - 3 = 18t
Equation to find the amount of time t it takes for you to catch up to your friend is 12t - 3 = 18t
Solving the equation
12t - 3 = 18t
Collect like terms
12t - 18t = 3
-6t = 3
t = 3/-6
= -0.5
t = 1/2 hour
Time can not be negative, therefore it will take 1/2 an hour to catch up with your friend