Surface area of a cube = 486 square inches
Solution:
Given each side of a cube = 9 inches
Net of a cube has 6 squares.
Area of square = side × side
Area of 1 square = 9 × 9 = 81 square inches
Surface area of a cube = Area of 6 squares
= 6 × (side × side)
= 6 × 81
= 486 square inches
Hence, surface area of a cube is 486 square inches.
Answer:
Step-by-step explanation:
Answer:
Let the number be n.
3n - 4= -15
3n= -15+4
3n= -11
n= -11/3
n= -3.67 or n= -3 2/3
Step-by-step explanation:
Bring over 4 to the RHS of the equation and divide the RHS by 3.
A) Find KM∠KEM is a right angle hence ΔKEM is a right angled triangle Using Pythogoras' theorem where the square of hypotenuse is equal to the sum of the squares of the adjacent sides we can answer the
KM² = KE² + ME²KM² = 8² + (3√5)² = 64 + 9x5KM = √109KM = 10.44
b)Find LMThe ratio of LM:KN is 3:5 hence if we take the length of one unit as xlength of LM is 3xand the length of KN is 5x ∠K and ∠N are equal making it a isosceles trapezoid. A line from L that cuts KN perpendicularly at D makes KE = DN
KN = LM + 2x 2x = KE + DN2x = 8+8x = 8LM = 3x = 3*8 = 24
c)Find KN Since ∠K and ∠N are equal, when we take the 2 triangles KEM and LDN, they both have the same height ME = LD.
∠K = ∠N Hence KE = DN the distance ED = LMhence KN = KE + ED + DN since ED = LM = 24and KE + DN = 16KN = 16 + 24 = 40
d)Find area KLMNArea of trapezium can be calculated using the formula below Area = 1/2 x perpendicular height between parallel lines x (sum of the parallel sides)substituting values into the general equationArea = 1/2 * ME * (KN+ LM) = 1/2 * 3√5 * (40 + 24) = 1/2 * 3√5 * 64 = 3 x 2.23 * 32 = 214.66 units²
