I hope this helps you
distance=speed×time
first cars time t
second cars time t+3
same distance
distance=55.t
distance=40. (t+3)
55t=40 (t+3)
55t-40t=120
15t=120
t=8
t+3=11
This is simply a question about ratios. This ratio means that for every 1 cm on the map, there are 12 km in actuality. You can set this problem up in fractions:
1 cm 12 cm
-------- = ----------
12 km x
To solve for x, we cross-multiply, for the moment ignoring units. Remember, your answer will be in km.
1*x=12*12
x=144
If x=144, then for 12 cm, there are 144 km.
Answer:
(-4,4)
Step-by-step explanation:
-5x-10y=-20
10x+10y=0
divide both sides by 2
-5x-10y=-20
5x+5y=0
that makes
-5y=-20
divide both sides by -5
y=4
now substitute 4 for y
10x+10 x 4=0
multiply
10x+40=0
subtract
10x=-40
divide
x=-4
