If 6 also had the -2 exponent answer would be D if not then A
The surface area of the pyramid will be given as follows:
Area of triangles:
A=1/2×base×height
A=1/2×12×18
A=108 m²
Area of 6 triangles is given by:
A=108×6=648 m²
Area of the hexagon:
A=6×1/2×12×6√3
A=374.123m²
Total surface area:
SA=648+374.123
SA=1022.123 m²~1022 m²
Answer: C] 1022 m²
Answer:
The speed on motorboat is 20 mph
Step-by-step explanation:
here, we want to find the speed on the motorboat
if he has a speed of x mph on the motor boat, his speed on the ski will be (x + 10) mph
The total hours is 4 hours
Mathematically; speed = distance/time
Time on ski is 27/x+ 10
Time on motor boat is 62/x
The addition of both is 4
Thus;
27/(x + 10) + 62/x = 4
27(x) + 62(x + 10) = 4(x)(x + 10)
27x + 62x + 620 = 4(x^2 + 10x)
89x + 620 = 4x^2 + 40x
4x^2 -49x-620 = 0
using the quadratic formula;
{-b ± √(b^2-4ac)}/2a
where a = 4, b = -49 and c = -620
= 49 ± √(-49)^2-4(4)(-620)/8
So we have
49+ 111/8 or 49-111/8
Speed cannot be negative
(49 + 111)/8
= 20 mph
Answer:
12.8km/hr
Step-by-step explanation:
Distance = 76.8km
Time = 6 hours
Speed = distance ➗ time
Speed = 76.8km ➗ 6 hours
Speed = 12.8km/hr
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