To answer the problem above, use the concept of ratio and proportion. The ratio between 1 cm to 21 km should be the same as the ratio of 3.1 cm to the actual distance. Let x be the unknown actual distance and mathematically express the situation,
(1 cm/ 21 km) = (3.1 cm / x km)
This equation gives a value for x which is 65.1 km. Therefore, the answer is letter C.
(0,-3) because that’s what it is
Answer:
48+14i
Step-by-step explanation:
So squaring (i+7) looks like this
(i+7)^2
(i+7)(i+7)
Use foil.
First: i(i)=i^2=-1
Outer: i(7)=7i
Inner: 7(i)=7i
Last: 7(7)=49
____________Add the terms.
48+14i
Remark
Writing down the givens for these questions is almost a command. You must know which equation of the big 4 to use. The givens + what you want to find will determine the equation.
Givens
vi = 30.7 km/hr = 30.7 km/hr *[1000m/1km]*[1hr/3600sec] = 8.52m/sec
vf = 120 km/hr = 120 km/hr * [1000 m/1 km]*[1h/3600 sec] = 33.3 m/s
t = 4.9 seconds
d = ???
Formula
d = (vi + vf)*t/2
Solve
d = ( 33.3+8.52 )*4.9/2
d = (41.85333)*4.9/2
d = 205.02/2
d = 102.51 m<<<Answer