Answer:
x = 5 , y = 15
Step-by-step explanation:
You can solve this using substitution.
Let the quantity of cheese wafers be denoted by x and the quantity of chocolate wafers denoted by y
2x + 1y = 25
x + y = 20
These two equations are the answer to part A, (remember to include the above prompt which says what x and y denote).
For part B I used substitution because it was more applicable to the question then addition or elimination.
ACTUAL WORK
Set 2x + 1y = 25 equal to x
x = 25 - y / 2
Replace x with y in the second equation
(25 - y / 2) + y = 20
And solve for y
y = 15
Since we know what y is we can replace y in the second equation and find what x is
x + 15 = 20
Solve for x
x = 5
The sister catches up Jeff after 2 hours
Step-by-step explanation:
We can write Jeff's position and his sister position at time t using the following expressions:
- Jeff position:

where:
7 is the initial position of Jeff when his sister sarts chasing him
2.5 is Jeff's velocity (in miles/hour), so its position increases by 2.5 miles for each hour
t is the time measured in hours
- Sister position:

where
6 is the sister velocity (her position increases by 6 miles for every hour)
t is the time measured in hours
The sister catches up Jeff when the two positions are equal, so

And solving for t,

So, the sister catches Jeff after 2 hours.
Learn more about speed:
brainly.com/question/8893949
#LearnwithBrainly
Answer:
295000
Step-by-step explanation:
hope this helps