Answer:
n = 7
n = -3
Step-by-step explanation:
4n+6 = n²-15
4n = n² - 21
n² - 4n - 21 = 0
(n-7)(n+3) = 0
n = 7
n = -3
Answer:
B
Step-by-step explanation:
Use photo math it works very well!
Solution: We are given that:
5 people can paint 7 walls in 21 minutes
Therefore, 1 person can paint 7 walls in
minutes
Which means 1 person can paint 1 wall in
minutes
Now, 3 people can paint 1 wall in
minutes
Therefore, 3 people can paint 5 walls in
minutes