9514 1404 393
Answer:
a) w(4w-15)
b) w²
c) w(4w -15) = w²
d) w = 5
e) 5 by 5
Step-by-step explanation:
a) If w is the width, and the length is 15 less than 4 times the width, then the length is 4w-15. The area is the product of length and width.
A = w(4w -15)
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b) If w is the side length, the area of the square is (also) the product of length and width:
A = w²
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c) Equating the expressions for area, we have ...
w(4w -15) = w²
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d) we can subtract the right side to get ...
4w² -15w -w² = 0
3w(w -5) = 0
This has solutions w=0 and w=5. Only the positive solution is sensible in this problem.
The side length of the square is 5 units.
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e) The rectangle is 5 units wide, and 4(5)-15 = 5 units long.
The rectangle and square have the same width and the same area, so the rectangle must be a square.
n>-6 and n<3 (there's your answer my friend)
Answer:
b for top and c for botam
Step-by-step explanation:
Answer:
Your answer is going to be 14.54. 16.99 off of 7% sales tax is $18.18, but 20% off is $14.54.
Answer:
DL/dt = 17 mph
Step-by-step explanation:
The ships and the port shape a right triangle
Ship going west ( x-direction) is traveling at 15 mph
Ship going north (y-direction) is traveling at 10 mph
The distance L between ships is:
L² = x² + y²
Tacking derivatives on both sides of the equation with respect to time
we get
2*L*DL/dt = 2*x*Dx/dt + 2*y*Dy/dt (1)
In that equation we know:
Dx/dt = 15 mph
Dy/dt = 10 mph
At the moment ship traveling from the east is at 3 miles from the port
then x = 3 m and the other ship is at 4 miles north
then by Pythagoras theorem
L = √ 3² + 4² L = 5
By substitution in equation 1
2*5*DL/dt = 2*3*15 + 2*4*10
10* DL/dt = 90 + 80
DL/dt = 170 / 10
DL/dt = 17 mph
