Answer:
D
Step-by-step explanation:
D is the correct answer
Explanation:
Let the equation be
a
⋅
x
2
+
b
⋅
x
+
c
. To factorize multiplication of a and c i.e. ac so that sum of factors, if ac is positive (and difference if ac is negative) is equal to b. Now split b into these two components and factorization will be easy.
For the answer to the question above, we'll have to use the formula for velocity which is v =<u> d
</u> t and d = vt
Since the total distance is given, therefore we can get the time and it will look like this.
220t + 250t = 1880
<u>470t</u> = <u>1880
</u>470 470
the problem indicates that the train runs 250kph
Let's substitute:
d = 250(4)
the distance traveled by Lian is 1000km
<u>
</u>