d=3.2(t+1)(2t−3)An air pump increases the oxygen levels in an aquarium and reduces the build-up of waste materials. The equation shown gives the depth, d, in inches of an air bubble beneath the surface of the water t seconds after it emerges from the air pump. After how many seconds does the air bubble reach the surface?
Q. d=3.2(t+1)(2t−3)An air pump increases the oxygen levels in an aquarium and reduces the build-up of waste materials. The equation shown gives the depth, d, in inches of an air bubble beneath the surface of the water t seconds after it emerges from the air pump. After how many seconds does the air bubble reach the surface?
Understand the Problem: Understand the problem.We are given an equation d=3.2(t+1)(2t−3) that represents the depth of an air bubble in an aquarium as a function of time t. We need to find out when the air bubble reaches the surface. The surface is represented by a depth of 0 inches.
Set Depth to 0: Set the depth d to 0 to find when the bubble reaches the surface.We need to solve the equation 0=3.2(t+1)(2t−3) for t.
Factor Out Constant: Factor out the constant 3.2. Since 3.2 is a constant multiplier, we can divide both sides of the equation by 3.2 to simplify our equation. This gives us 0=(t+1)(2t−3).
Apply Zero Product Property: Apply the zero product property.The zero product property states that if a product of two factors is zero, then at least one of the factors must be zero. Therefore, we set each factor equal to zero: t+1=0 and 2t−3=0.
Solve First Factor: Solve the first factor for t. Solving t+1=0 for t gives us t=−1.
Solve Second Factor: Solve the second factor for t. Solving 2t−3=0 for t gives us 2t=3, which simplifies to t=23 or t=1.5.
Evaluate Solutions: Evaluate the solutions.The solution t=−1 does not make sense in this context because time cannot be negative. Therefore, we discard this solution. The solution t=1.5 seconds is the time when the air bubble reaches the surface.
More problems from Write exponential functions: word problems