Try this solution:
cos4xcos3x+sin4xsin3x=cos(4x-3x)=cosx.
Answer: C
Answer:
Step-by-stefdfgp explanation:
Answer:
22 and a half weeks
Step-by-step explanation:
We are told that Nilda owes $250 and has been earning $25 per week to catch up and start saving.
Also, Karla has saved $200 and has been saving an extra $5 per week to slowly build her savings.
Let the number of weeks they save for be represented as x.
Therefore, for them to have the same amount of money after x weeks,
25x - 250 = 200 + 5x
The left hand side represents Nilda's situation (250 is being deducted because she owes $250) while the right hand side represents Karla's situation (the 200 is added because she already owns $200).
Solving for x:
25x - 250 = 200 + 5x
Collecting like terms:
25x - 5x = 250 + 200
20x = 450
x = 450 / 20 = 22.5 weeks
Hence, they would both need to save for 22 and a half weeks to have the same amount of money.
On the last day she needs to travel 64 miles
To expand
X times X = X^2
-2 times X = -2X ( add this to 4X to equal 2X)
4 times X = 4X
-2 times 4 = -8
X^2 + 2X -8
To solve when equation = 0
X = +2 or -4