Answer:
The dimensions of the original rectangle are Length =12cm, Width=8cm
Step-by-step explanation
Let the length of the rectangle be x
Let the width of the rectangle be y
The perimeter of a rectangle is 40cm.
2(x+y)=40
Divide both sides by 2
x+y=20
If the length were doubled(2x) and the width halved(y/2), the perimeter would be increased by 16cm,i.e.(40+16)cm
Therefore:
Divide both sides by 2
From the first equation, x=20-y.
Substitute x=20-y into
Answer:
Step-by-step explanation:
First find the surface area of the clyinder and find the area circles and subtract
Then find the surface area of a cone, remove the circle area and double it.
Clyinder surface area (without circle area) 2πrh+2πr2=2·π·4·6+2·π·42≈251.32741
251.32741 - 50.2 - 50.2
Cone area: A=πr(r+h2+r2)=π·4·(4+32+42)≈113.09734
113.09734 - 50.2 - 50.2
Total: 12.69734 + 150.92741 = 163.62475
Answer:
the first three are the answer
Step-by-step explanation:
Answer:
285 words
Step-by-step explanation: