The value of the coefficient B is 9.
2(x+By)(x-2y)
=2(x^2 -2xy +Bxy -2By^2)
=2x^2 -4xy + 2Bxy - 4By^2
The original form is 2x^2 + 14xy - 36y^2
-36y^2 = -4By^2
B= 9
-4xy +2Bxy= 14xy
xy(-4 +2B)= 14xy
-4 + 2B = 14
2B = 18
B=9
Answer:
50 rpm clockwise
Step-by-step explanation:
100/50 × 50/200 × 200/150 × 150/200 = 0.5
In an odd number of gears, the first and last rotate inthe same direction.
100 rpm × 0.5 = 50 rpm
Answer: 50 rpm clockwise
To solve this problem we can make the following rule of three
6 ---> 3/4
x ----> 1
Clearing x we have:
x = (1/3/4) * (6)
x = (4/3) * (6)
x = 24/3
x = 8
Answer:
Carlos climbs 8 miles for every mile Lara climbs.
Answer:
12/28
Step-by-step explanation:
3 x 4 = 12
7 x 4 = 28
Answer:
3:7
Step-by-step explanation:
So to solve this problem, you have to understand what the ratio 1:4 and 2:3 means. The 1:4 ratio in the first equation means that for "each unit of alcohol" there is 4 of those units of water. So let's say I had 2 gallons of alcohol and mixed it with 8 gallons of water. This means for each gallon of alcohol, there is 4 gallons of water, or in other words a 1:4 ratio. This can be described as a percentage as well. For each 5 gallons there are 4 gallons of water, and 1 gallon of alcohol or <em>20%</em> is alcohol. So let's just say that x=alcohol and y=water, this means that: 
where c is the total amount in the glass. This means that: 
Let's do the same thing to the second equation. the ratio means that for every 2 units of alcohol there are 3 units of water. This means for every 5 gallons of the mixture there is 2 units of alcohol which is 40%. In this case let's also say that j=alcohol and k=water. This means that: 
and that: 
.
So if we're going to add the two glasses, we simply add the two sides, and get: 
. Now remember how can can express j and x in terms of c, since it's a certain percentage of c (the entire thing). This means that we get: 
Now we can add like terms to get the equation: 
. We can find how much 0.6c is to 2c by dividing the 2, in doing so we get that 0.6c/2c = 0.3, or in other words the 0.6c is only 30% of the final mixture, and since the 0.6c represents the alcohol in this mixture, that means that's the percentage of alcohol. To write this as a ratio, this means for every 3 units of alcohol, there is 7 units of water, because 3/10 = 30%.
