Answer: Rate of change of Area of the triangle = 2.75cm~/min
Step-by-step explanation:
If the present height of the triangle is 22cm and the height increases by 5cm/min. It means the height was 2cm four minutes earlier: 5cm for 1st min + 5cm for 2nd min + 5cm for 3rd min + 5cm for 4th min = 20cm after 4min.
Therefore height equals 22 - 20 = 2cm four minutes earlier.
Using the same four minutes for the base. Since the base shrinks at 1cm/min, for the base to shrink to 10cm it means it was 14cm four minutes earlier.
The Area of a triangle is given by
A = 1/2 × base × height
Therefore Area= 1/2× 10×22 = 110cm~
Since it took four minutes to get to this area, the rate of change of the area will be 110÷4 = 2.75cm~/min
It’s B
Good luck!! Hope this helps
L= 2w+30
Perimeter= 2(l+w)
Substitute in the length above
P=2 ((2w+30) + w)
Remember order of operations. You must multiply everything by 2 before adding.
P=4w+60+2w
P=6w+60
Hello!
The surface area of a sphere is found by using the formula: SA = 4πr².
Figure 1
In the first figure, the radius is given which is 18 meters. With that, we can substitute the value of the radius into the formula and solve.
SA = 4π(18)²
SA = 4(324)π
SA = 1296π, 4071.50 (multiplied by π), 4069.44 (multiplied by 3.14)
Therefore, the surface area of figure one is 1296π m².
Figure 2
In the second figure, the diameter of the circle is given. The radius is half the diameter, so to find the radius, you need to divide the diameter by 2.
14 mm / 2 = 7 mm
With that, we can find the surface area of figure two, using the formula.
SA = 4π(7)²
SA = 4(49)π
SA = 196π, 615.75 (multiplied by π), 615.44 (multiplied by 3.14)
Therefore, the surface area of figure two is 196π mm².