To solve this problem,you need to use the formula d = rd (distance = rates x time)She runs at a speed of 7 mph and walks at a speed of 3 mph. Her distance running is d = 7trwhere tr is the time she spends running Her distance walking isd = 3twwhere tw is the time she spends walking The distances are the same so7tr = 3tw We also know that the total time is 4 hourstr + tw = 4tr = 4-tw Substitute this value of tr in the first equation7tr = 3tw7(4-tw) = 3tw28-7tw = 3tw28 = 10tw2.8 = tw Denise will spend 2.8 hours (2 hours, 48 minutes) walking back and 1.2 hours (1 hour, 12 minutes running.
Hope I helped :)
<span>y=-4/x+1 is ambiguous, since it's not immediately clear whether you meant
-4
y = -4/x + 1 or y = ---------
x+1
I'm going to assume that the latter is what you meant.
1. Interchange x and y, obtaining:
-4
x = --------
y+1
2. Solve this for y, obtaining y+1 = -4/x, or xy + x = -4, or
-x - 4
xy = -x-4, or y = ---------
x
-1 -1 4
3. Replace y with f (x): f (x) = -1 - -----
x
This last result has the correct form.</span>
At the bank, Derek made 7 withdrawals, each in the same amount. His brother, John, made 5 withdrawls, each in the same amount.
Let x be the amount of one of Derek's withdrawals
Each of John's withdrawals was $5 more than each withdrawal that Derek made.
x + 5 is t the amount of one of John's withdrawals
Derek made 7 withdrawals
So amount withdraw 7 times = 7x
John made 5 withdrawals
So amount withdraw 5 times = 5(x+5)
Both Derek and John withdrew the same amount of money in the end
(A) 7x = 5(x+5)
(B) Solve for x
7x = 5x + 25
Subtract 5x from both sides
2x = 25
Divide by 2
x = 12.5
(C) check your solution
we plug in 12.5 for x in 7x= 5x + 25
7(12.5) = 5(12.5) + 25
87.5 = 62.5+ 25
87.5 = 87.5
(D) Each brother withdrawal 87.5 dollars
There is 8 fruits in set A and 7 in set B
Your answer would be A because $4800 is your starting number and it increases 2% every year. How much is it in 20 years?
You use the formula ab^x
a is your starting number
b is the percentage
x is always the length of time
Since you are increasing and trying to get its worth larger than what it was before you use a number larger than one hundred percent in this case the number would be 1.02.
Y=4800(1.02)^20
Y=$7132.55
