Answer:
9x, 8x+12
Step-by-step explanation:
x(2x+7)-2x(x-1)
=> 9x
Answer: 5/1 or just 5
Step-by-step explanation:
Answer:
d = 7.4 cm is the distance between the two cities on the map.
Step-by-step explanation:
Let d = the distance measured on the map in centimeters (cm) between any two locations and let D be the actual distance in kilometers (km) between these same two locations.
Since the scale on the map is 1 cm = 45 km, then the ratio of the distance on the map to the actual distance is equal to 1cm/45 km; therefore the quotient of any measured distance d on the map divided by the corresponding much longer actual distance D would have to maintain (equal) this same ratio; In other words, we can set up the following proportion to solve for d given the actual distance D = 333 km as follows:
1 cm/45 km = d/D
Substituting, we get:
1 cm/45 km = d/333 km
d/333 km = 1 cm/45 km
(d/333 km)(333 km) = (1 cm/45 km)(333 km)
d = (333 km/45 km)(1 cm)
d = 7.4 cm is the distance between the two cities on the map.
Check:
1 cm/45 cm = d/333 km
1 cm/45 cm = 7.4 cm/333 km
1 cm/45 cm = 1 cm/45 km (Therefore, the distance ratio of the map has been maintained
Answer:
Step-by-step explanation:
cos (x/2)=cos x+1
cos (x/2)=2cos ²(x/2)
2 cos²(x/2)-cos (x/2)=0
cos (x/2)[2 cos (x/2)-1]=0
cos (x/2)=0=cos π/2,cos (3π/2)=cos (2nπ+π/2),cos(2nπ+3π/2)
x/2=2nπ+π/2,2nπ+3π/2
x=4nπ+π,4nπ+3π
n=0,1,2,...
x=π,3π
or x=180°,540°,...
180°∈[0,360]
so x=180°
or
2cos(x/2)-1=0
cos (x/2)=1/2=cos60,cos (360-60)=cos 60,cos 300=cos (360n+60),cos (360n+300)
x/2=360n+60,360n+300
x=720n+120,720n+300
n=0,1,2,...
x=120,300,840,1020,...
only 120° and 300° ∈[0,360°]
Hence x=120°,180°,300°
