Answer: Train A = 50 mph; Train B = 30 mph
Step-by-step explanation:
In this case, let's call the speed of both trains as:
Va: speed of train A
Vb: speed of train B
As train A is faster than train B, let's call speed of train B as X; So if Vb is X, then Va would be:
Vb = X
Va = X + 20
If we combine both Speed, we have:
V = Va + Vb = X + X + 20 = 2X + 20
Now that we have an expression for the combined speed, let's recall the formula for speed in general:
V = d/t
Where:
d: distance = 240 miles
t: time = 3 hours
Combining all the data we have:
V = 240/3
but V is 2X + 20 so:
2X + 20 = 240/3
Solving for X:
2X + 20 = 80
2X = 80 - 20
2X = 60
X = 60/2
X = Vb = 30 mph
Now that we know speed of one train, we can know the speed of the other train:
Va = 30 + 20 = 50 mph
Perimeter of this triangle
= (8 + 9 + 13) units
= 30 units
Answer:
(y - 3)² = 12(x + 3)
Step-by-step explanation:
The focus is to the right of the vertex, so the parabola is sideways and opens to the right.
The conic form of a sideways parabola is
(y - k)² = 4p(x - h)
The vertex is at h = -3; k = 3
The focus is at (h + p, k) = (-3 + p, 3)
The vertex and focus are three units apart, so p = 3.
The equation of your parabola is
(y - 3)² = 12(x + 3)
The figure below shows the graph of your parabola with its focus and vertex.
Answer:
12 Marshmellow weight=7.2×12=86.4grams
721,000 should be the answer. took me a little while though haha
