Ah okay so in differential equations you usually want the top variable isolated. To do this, multiply by dt and 2u and you get

Now just integrate both sides. The integral of 2u with respect to u is u². The integral of (2t + sec²(t) with respect to t is t² + ∫sec²(t)dt. The last part is just tan(x) because d/dt(tan(t)) is sec²(t) so just integrating gets us back. Now we have

Where c and k are arbitrary constants. Subtracting c from k and you get

Where b is another constant. To find b, just plug in u(0) = -1 where u is -1 and t is 0. This becomes

tan(0) is 0 so b = 1. Take the plus or minus square root on both sides and you finally get

But Brainly didn't let me do but juat remember there is a plus or minus square root on the left.
Answer
Mandisa uses more balloon per animal.
Amira and Mandisa made the same amount of balloon animals.
Explanation
Mandisa uses 5 balloons per animal.
You can find this out by putting the difference between two of the y values (output, dependent variable, in this case balloons) over the difference between two of the x values (input, independent variable, in this case animals). Let's take 225 and 125 from the y value and 20 and 40 from the x value. Mandisa uses 225-125=100 balloons per 40-20=20 animals. Mandisa uses 5 balloons per animal. 5 is more than 4 (how many balloons Amira uses for each animal), so Mandisa uses more balloons per animal.
Amira and Mandisa made the same amount of balloon animals.
Now you can divide the number of balloons they had at the beginning by the number of balloons per animal to find out how many animals each person made. Amira started with 260 balloons and used 4 balloons for each animal. Amira made 260/4=65 animals.
If Mandisa used 100 balloons to make 20 animals, she would have had 225+100=325 balloons at the beginning. Mandisa made 325/5=65 animals.
The designer must sell 200 hats for breaking even.
Step-by-step explanation:
Given,
Cost for material for each hat = $5.50
Selling price of each hat = $12.50
Cost spend on advertising = $1400
Let,
x represents the number of hats.
Revenue = 12.50x
Costs = 5.50x+1400
For breaking even,
Revenue = Cost

Dividing both sides by 7

The designer must sell 200 hats for breaking even.
Keywords: addition, division
Learn more about division at:
#LearnwithBrainly
Answer:

Step-by-step explanation:
Answer: i'd say c
Step-by-step explanation: