Draw a diagram! Lets say the width is x, then the length must be 2x.
Area = length x width
2x x x = 8sq meters
2x^2 = 8
x^2 =4
x = √4
x = 2
we found the width the length is two times the width, making it 4 meters.
Percent decrease : (original number - new number) / original number)...x 100
(13.00 - 7.50) / 13.00 = 5.5/13 = 0.42....x 100 = 42% decrease
49/100 in simply that is your answer
Answer:
1. Multiply the value of the first variable by one of the original equations to solve for the second variable.
2. Solve for one of the variables.
3. Substitute the value of the known variable into one of the original equations to solve for the unknown variable.
Step-by-step explanation:
Answer:
17.9 m/s
Step-by-step explanation:
Volume of the slick = 0.5 x π r² h--------------------------------- (1)
Where r = radius of slick
h = thickness of slick, 10⁻⁶m
If 0.5m³ of oil leaked, then the radius of the semicircular slick can be calculated from equation (1)
V = 0.5 x π r² h
0.5= 0.5 x π x r² x 10⁻⁶
r² = 10⁶/ π
r = 10³/√π
dV/dt = πrh dr/dt + 0.5π r² dh/dt----------------------------------- (2)
Asumming the film thickness is constant , equation (2) becomes
dV/dt = πrh dr/dt-------------------------------- (3)
dV/dt = 0.1m³/day
r= 10³/√π
dr/dt= rate of expansion of the slick
Substituting into (3);
0.1 = π x 10³/√π x 10⁻⁶ x dr/dt
dr/dt = 0.1 x 10⁶/ ( π x 10³/√π)
= 17.9479 m/s
≅ 17.9 m/s