Answer:
<h2>
70cm/s</h2>
Step-by-step explanation:
Area of a square with side of length L is expressed as A = L². The rate at which the area is increasing will be expressed as dA/dt.
dA/dt = dA/dL * dL/dt where
dL/dt is the rate at which each side of the square is increasing.
Since dA/dL = 2L, dA/dt = 2L dL/dt
Given dL/dt = 5cm/s and the Area of the square = 49 cm²
49 = L²
L = √49
L = 7cm
dA/dt = 2(7) * 5
dA/dt = 14*5
dA/dt = 70cm/s
The rate at which the area of the square is increasing is 70cm/s
Let i = sqrt(-1) which is the conventional notation to set up an imaginary number
The idea is to break up the radicand, aka stuff under the square root, to simplify
sqrt(-8) = sqrt(-1*4*2)
sqrt(-8) = sqrt(-1)*sqrt(4)*sqrt(2)
sqrt(-8) = i*2*sqrt(2)
sqrt(-8) = 2i*sqrt(2)
<h3>Answer is choice A</h3>
Answer: it will cost $280
Step-by-step explanation:
The diagonal of the rectangular garden divides it into two equal right angle triangles. The diagonal represents the hypotenuse of each right angle triangle. The length and width of the rectangle represents the adjacent and opposite sides of the right angle triangle. To determine the length of the diagonal, d, we would apply Pythagoras theorem which is expressed as
Hypotenuse² = opposite side² + adjacent side²
Therefore
d² = 24² + 32²
d² = 576 + 1024 = 1600
d = √1600
d = 40 feet
If the path is 2 feet wide, then the area of the path is
Area = 40 × 2 = 80 ft²
If gravel costs $3.50 a square foot, then the cost to install the gravel path is
3.5 × 80 = $280
