Answer:
Train A - 50 miles per hour
train B - 30 miles per hour
Step-by-step explanation:
Let x mph be the speed of the train B, then the speed of the train A is (x+20) mph.
In 3 hours,
- train A travels 3(x+20) miles
- train B travels 3x miles
In total, they covered the distance of 240 miles, so
![3(x+20)+3x=240\ \ \ \text{[Divide by 3]}\\ \\x+20+x=80\\ \\2x=80-20\\ \\2x=60\\ \\x=30\ mph\\ \\x+20=30+20=50\ mph](https://tex.z-dn.net/?f=3%28x%2B20%29%2B3x%3D240%5C%20%5C%20%5C%20%5Ctext%7B%5BDivide%20by%203%5D%7D%5C%5C%20%5C%5Cx%2B20%2Bx%3D80%5C%5C%20%5C%5C2x%3D80-20%5C%5C%20%5C%5C2x%3D60%5C%5C%20%5C%5Cx%3D30%5C%20mph%5C%5C%20%5C%5Cx%2B20%3D30%2B20%3D50%5C%20mph)
Answer:
D(1, –5), (7, 1), (–11, 7)
Step-by-step explanation:
The given inequalities are:
y + x ≥ –4
y ≥ x – 6
3y + x ≤ 10
We graph the inequalities as shown in the attachment.
The coordinates of the vertices of the figure formed by the given system of inequalities are:
(1, –5), (7, 1), (–11, 7)
The correct choice is D.
Answer: 3/5
Step-by-step explanation: To find the reciprocal of 1 and 2/3, we first need to convert 1 and 2/3 to an improper fraction.
To write a mixed number as an improper fraction, first multiply the denominator times the whole number, then add the numerator.
So here, we multiply the denominator, 3, times the whole number, 1, then we add the numerator. So we have (3 x 1) + 2 or 3 + 2 which is 5.
Now we put our new number over our old denominator and we get 5/3.
However, we're not done yet. We still need to find the reciprocal.
The reciprocal describes a fraction so when we're asked to find the reciprocal of 5/3, we want to switch the numerator and denominator.
So if we switch 5/3, we get the proper fraction 3/5.
Therefore, the mixed number 1 and 2/3 is equivalent to the improper fraction 5/3, and if we switch the top and bottom numbers, we get 3/5.
U just need to turn the diagram to the way you can understand it