Answer:
See below
Step-by-step explanation:
Answer:
the ball takes 3.1944 sec
Step-by-step explanation:
We can use a variable equation to solve this. Let A represent alan's age, B represent bob's age, and C represent Cindy's age. So Bob's age would be Alan's age - 5, or a -5 = B. Then Bob's age would be double Cindy's age, so that means 2 multiplied by Cindy's age = Bob's age, or 2C = B. Your two equations are:
A - 5 = B
2C = B
Also a third equation that helps is A + B + C = 20.
Finally, here are the ages.
Alan = 11 years old
Bob = 6 years old
Cindy = 3 years old.
PS: Sorry, I'm not that good at explaining things, but here are the answers
Since both start with y, we can set them equal to each other. 2x+7 = -4x - 5. This means we add 4x to both sides, 6x + 7 = -5. Then we subtract 7 from both sides, 6x = -12. Finally we divide both sides by 6, and x = -2.