Answer:
15 hours
Step-by-step explanation:
9 lawns is 3 times as much as 3 lawns
it will take 3 times as long
3 * 5 hours = 15 hours
Answer:

Step-by-step explanation:

Here



Answer:
The first step is to replace the y in y-x=15 with 7x (we can do this because the first equation tells us that they're equal)
solve and get
(2.5,17.5)
or x= 2.5 y=17.5
Step-by-step explanation:
The first step is to recognize that y=7x which means that we can just replace the y in the second equation with 7x
7x-x=15
6x=15
x=2.5
Then we can solve for y
y=7(2.5)
y=17.5
C because it is icoceles.