Length of train : 100
length of bridge : 400
distance covered by the train to cross the bridge : (100 + 400) = 500
time taken by the train to cross : 30
speed = distance / time
speed = 500/30
speed = 16.67 meters per second <===
It would be 10 bc ten is the next number i guess
Answer:
x=-7/9, y=4/3. (-7/9, 4/3).
Step-by-step explanation:
6x+2y=-2
3x-2y=-5
-----------------
9x=-7
x=-7/9
6(-7/9)+2y=-2
-42/9+2y=-2
2y=-2-(-42/9)
2y=-2+42/9
2y=-18/9+42/9
2y=24/9
y=(24/9)/2
y=(24/9)(1/2)
y=24/18
y=4/3
(x+2y+z) (x-2y-z)
= x^2 - 2xy - xz + 2xy - 4y^2 - 2yz + xz - 2yz - z^2 = x^2 - 4y^2 - 4yz -z^2
Hope it helped!
Answer:
42+7xy=(7*6)+(7xy).......