I=PRT/100
1. Make R (rate) subject
R/100= I/PT
2. Substitute and calculate
r/100= i/pt
r/100= 40/400 × 1
(<em>4</em><em>0</em><em> </em><em>i</em><em>s</em><em> </em>from 440-400.<em>T</em><em>h</em><em>e</em><em> </em><em>i</em><em>n</em><em>t</em><em>e</em><em>r</em><em>e</em><em>s</em><em>t</em>)
r/100= 0.1
r/100×100= 0.1×100
r=10% (interest rate per year)
To confirm
I=PRT
I= 400×10/100×1
I= $40 (Interest)
Looks like the graph is decreasing to me
Surface area of the cylinder = 816.4 sq. ft.
Solution:
Height of the cylinder = 21 ft
Diameter of the cylinder = 10 ft
Radius of the cylinder = 10 ÷ 2 = 5 ft
Use the value of
= 3.14
Surface area of the cylinder = 
Substitute the given values in the surface area formula, we get
Surface area of the cylinder 

ft²
Hence the surface area of the cylinder is 816.4 sq. ft.
The height is 9.875 feet from which the goalkeeper catches the ball.
The player kicks soccer from a height of 2 feet
x = 0 and y = 2
Maximum height of 20 feet after traveling 40 feet
x = 40, y = 20
So let y = a(x - 40)² + 20 ( the path of parabola)
Since x = 0 , y = 2
So, 2 = a(0 - 40)² + 20
2 = 1600a + 20
-18 = 1600a
a = - 9/800
Thus, y = -9/800(x - 40)² + 20
Since the soccer is caught by the goalkeeper 70 feet from where it was kicked
x = 70
So at this time,
y = -9/800 ( 70 - 40)² + 20
= -9/800 × 900 + 20
= - 81/8 + 20
= 79/ 8
= 9.875 feet
Therefore the height at which the goalkeeper catches the ball is 9.875 feet.
To know more about the height refer to the link given below:
brainly.com/question/27030273
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