geometry: area incr. by 5 same as twice area less 3
- Thread starter devnanji
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Re: geometry
This is really straight forward. No tricks.
the area of a rectangle increased by 5 is the same as 3 less than twice the area of the rectangle
Give things names.
Let "the area of the rectangle" be represented by A.
Now, you know that "is increased by 5" means that 5 is added to whatever is mentioned.
You also know that "is the same as" means "='.
Analyze the phrase "3 less than twice the whatever". Suppose the whatever is q. Then twice that is 2 times that or 2q. And 3 less than what we now have is that minus 3 or 2q-3.
Now, do some thinking. Put all this together and simply substitute what you have learned directly into the phrase " the area of a rectangle increased by 5 is the same as 3 less than twice the area of the rectangle". That should give you the equation. Solve for A and your problems are over.
This is really straight forward. No tricks.
the area of a rectangle increased by 5 is the same as 3 less than twice the area of the rectangle
Give things names.
Let "the area of the rectangle" be represented by A.
Now, you know that "is increased by 5" means that 5 is added to whatever is mentioned.
You also know that "is the same as" means "='.
Analyze the phrase "3 less than twice the whatever". Suppose the whatever is q. Then twice that is 2 times that or 2q. And 3 less than what we now have is that minus 3 or 2q-3.
Now, do some thinking. Put all this together and simply substitute what you have learned directly into the phrase " the area of a rectangle increased by 5 is the same as 3 less than twice the area of the rectangle". That should give you the equation. Solve for A and your problems are over.
mmm4444bot
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Re: geometry
The problem you posted does not necessarily have anything to do with either areas or rectangles.
In other words, here is the same problem:
A number increased by 5 is the same as 3 less than twice this number. Write and solve an equation to determine this number.
This problem has two basic parts. The first part is to write the equation which represents the given facts. The second part is to solve this equation.
Let's choose a variable name to represent this unknown number so that we have a symbol to use when we write the equation.
Let X = the unknown number
So now we have:
X increased by 5 is the same as 3 less than twice X
How do we write an equation to express the facts in this problem. One place to start would be to figure out what part of the sentence expressess the equal sign.
"is the same as" is the part of this sentence that makes a statement about equality.
In other words, the expression that comes before the phrase, "is the same as", EQUALS the expression that comes after the phrase, "is the same as".
So now we have:
X increased by 5 = 3 less than twice X
"X increased by 5" can be written as X + 5.
"twice X" can be written as 2x
"3 less than" something means that 3 is being subracted FROM that something.
3 less than 2x can be written as 2x - 3.
I hope that this is enough information for you to write an equation which represents the given facts:
X increased by 5 is the same as 3 less than twice X
I'm also going to guess, since you were not very specific on exactly why you cannot do this problem, that WRITING THE EQUATION is actually the only part on which you are stuck. In other words, I'm not going to say anything about how to solve the equation unless you ask because I first want to know that you understand the first part.
After you solve for X, then remember what the solution means. It's the area of the rectangle.
Let us know how it goes; PLEASE show your reasoning if you post a request for more help on this problem so that we can get some idea of what you're thinking.
Cheers,
~ Mark
devnanji said:
The problem you posted does not necessarily have anything to do with either areas or rectangles.
In other words, here is the same problem:
A number increased by 5 is the same as 3 less than twice this number. Write and solve an equation to determine this number.
This problem has two basic parts. The first part is to write the equation which represents the given facts. The second part is to solve this equation.
Let's choose a variable name to represent this unknown number so that we have a symbol to use when we write the equation.
Let X = the unknown number
So now we have:
X increased by 5 is the same as 3 less than twice X
How do we write an equation to express the facts in this problem. One place to start would be to figure out what part of the sentence expressess the equal sign.
"is the same as" is the part of this sentence that makes a statement about equality.
In other words, the expression that comes before the phrase, "is the same as", EQUALS the expression that comes after the phrase, "is the same as".
So now we have:
X increased by 5 = 3 less than twice X
"X increased by 5" can be written as X + 5.
"twice X" can be written as 2x
"3 less than" something means that 3 is being subracted FROM that something.
3 less than 2x can be written as 2x - 3.
I hope that this is enough information for you to write an equation which represents the given facts:
X increased by 5 is the same as 3 less than twice X
I'm also going to guess, since you were not very specific on exactly why you cannot do this problem, that WRITING THE EQUATION is actually the only part on which you are stuck. In other words, I'm not going to say anything about how to solve the equation unless you ask because I first want to know that you understand the first part.
After you solve for X, then remember what the solution means. It's the area of the rectangle.
Let us know how it goes; PLEASE show your reasoning if you post a request for more help on this problem so that we can get some idea of what you're thinking.
Cheers,
~ Mark