Answer:
6.8
Step-by-step explanation:
negative 2 times negative 3 is -6.
negative 2 times negative 0.4 is -0.8.
add them together :)
Answer:
11
Step-by-step explanation:
Unknown number = x
If twice the difference of x and 8 is 6:
2(x-8) = 6
2x-16 = 6
2x = 6 + 16
2x = 22
x = 22/2
x = 11
Answer from Gauthmath
answers
1) 70
2) 3,840
3) 24
4) 72
<u>Explanation</u>
Q1
The surface area of a cone is given by;
S.A = 2Πrl + Πr²
Where r is the radius of the base and l is the lateral height.
Πr² = area of the base = 20 in²
2Πrl = Area of the lateral surface
= 2.5 × 20
= 50
Area of the cone = 50 + 20
= 70 in²
Q2
The sides of the Pythagorean triangle with legs of 12 and 16.
The 3rd side will be;
c = √(12² + 16²)
= √400 = 20
Volume = 12 × 16 × 20
= 3,840
Q3
The volume of a cone is given by;
volume = 1/3 Π r² h
This shows that the volume of a cone is a third the volume of the cylinder.
∴ Volume of the cylinder = 12 × 3
= 24 ft³
Q4
The volume of any regular figure is;
Volume = base area × height
When the dimensions area usually 3. Let these dimensions be x, y and z.
∴ volume = x × y × z = 9
Doubling the dimensions;
Volume = 2x × 2y × 2z = 2 × 2 × 2 × 9
= 8 × xyz = 8 × 9
= 72 ft²
The circumference of a circle is given by: 2πr, where r is the radius of the circle. Equating 4π, we have 2πr = 4π so the radius of the circle is: r = 4/2 = 2. Then, the area of the circle is given by πr ^ 2 = π * (2 ^ 2) = 4π.Since the square and the circle have the same area, then: Let L be the side of the square, we have: L ^ 2 = 4π, clearing L = 2 * (π ^ (1/2))The perimeter of a square is the sum of its sides: P = L + L + L + L = 2 * (π ^ (1/2)) + 2 * (π ^ (1/2)) + 2 * (π ^ (1/2)) + 2 * (π) ^ (1/2)) P = 8 * (π ^ (1/2))
