The height that a ball reaches at a certain time t is given by the equation,
h = 2 - 15t + 5t²
We are asked to compute for the values of t that would allow the ball to reach a height of 7 meters.
Substitute the 7 to the equation,
7 = 2 - 15t + 5t²
Transposing,
5t² - 15t - 7 + 2 = 0
Simplifying,
5t² - 15t - 5 = 0
Divide the equation by 5,
t² - 3t - 1 = 0
The values of t can be calculated through the quadratic formula,
t = (-b +/- sqrt(b² - 4ac))/2a
Substituting,
t = (3 +/-sqrt (9 - 4(-1)) / 2(1)
t = 3.3 or t = -0.30
Since, we cannot have t as a negative number hence, our final answer is:
<em> t = 3.3 s</em>
Answer : because it is 3 units to the left of 2 on a horizontal number line
Answer:
i
Step-by-step explanation:
i
Volume is a three-dimensional scalar quantity. The cost of the glass is $1312.24.
<h3>What is volume?</h3>
A volume is a scalar number that expresses the amount of three-dimensional space enclosed by a closed surface.
Given the colony must be able to take a volume of 200,000 cubic meters, therefore, the diameter of the hemisphere will be,
The volume of Hemisphere = (2/3)πr³
200,000 = (2/3) × π × R³
R = 45.7
The area of the base of the hemisphere is,
Area of the base = πR² = π×(45.7) = 6561.185 meters²
Given the cost of glass is $0.20 per square meter, therefore, the cost of the glass of the base will be,
Cost of glass = 6561.185 × 0.20 = $1312.24
Hence, the cost of the glass is $1312.24.
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