Answer:

Step-by-step explanation:
When you multiply exponents together, you simply add them.
-8 + 3 = -5.
Train A speed= 70 km/h north
Train B speed= 75 km/h south
Opposite directions= add speeds 70+75=145
Distance= 435 Km
Time= d/s; 435/145= 3 hours
It would take 3 hours for the trains to be 435 kilometers apart
Answer:
after 6 days
Step-by-step explanation:
We can find the answer by solving the two equations simultaneously.
equation 1: y = -0.4x^2 +3xequation 2: x + y = 10
We need to write equation to with y as the subject:equation 2: y = 10 - x
equation 1 = equation 2:
10 - x = -0.4x^2 + 3x0.4x^2 - 4x + 10 = 02x^2 - 20 + 50 = 0(2x - 10)(x - 5) = 0x = -10/2 or x = 5
But x >= 0 (the question says it's a height above the water), so x = 5
Substituting x = 5 into one of the equations:
y = 10 - x
y = 10 - 5
y = 5
So the answer is C
Step-by-step explanation:
the numbers of the yellow and white counters
= 288- 38 = 250.
the ratio of yellow to white = 1:4
so,
the numbers of the yellow counters =
1/(1+4) × 250 =1/5 ×250 = 50
the numbers of the white counters =
4/(1+4) ×250 = 4/5 ×250 = 200
and the numbers of the red counters = 38