Answer:
x=7
Step-by-step explanation:
ln x +ln(x+1)=ln 56
ln x(x+1)=ln 56
so x(x+1)=56
x^2+x-56=0
(x+8)(x-7)=0
x= -8 or x=7
and lnx,x>0
so x=7
<span>potential; kinetic is the answer.</span>
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: 8 5/8 turns
Step-by-step explanation:
Hi, to answer this question we have to simply to multiply the number of turns that the windmill makes per hour (5 3/4) by the time asked (1 ½ hours).
Mathematically speaking:
5 3/4 x 1 1/2 = (5x4+3)/4 x (1x2+1)/2 = 23/4 x 3/2= 69/8 or 8 5/8 (mixed form)
In conclusion, the windmill makes 8 5/8 turns in 1 1/2 hours.
