need help with2^4 + 2^4 + 3^5 ...... Simplify

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need help with2^4 + 2^4 + 3^5 ...... Simplify

by nbpatel » Wed Nov 12, 2008 11:10 pm
I need help with this question:

2^4 + 2^4 + 3^5 +3^5 + 3^5

They somehow simplified it to tthis answer of 2^6 + 3^6

Also another similar question that I was having trouble with was:

2^(x) - 2^(x-2) = 3(2^13) what is the value of x

They got the answer of: 15`

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nbpatel wrote:I need help with this question:
( 2^4 + 2^4 ) + ( 3^5 +3^5 + 3^5 )

2x2^4 + 3*3^5 ( X^aX^b=X^(a+b))

2^5+3^6


nbpatel wrote:Also another similar question that I was having trouble with was:
2^(x) - 2^(x-2) = 3(2^13)


2^x-2^x/4 = (1-1/4) 2^x = 3/4 2^x = 3 2^13 = 2^(x-2)=2^13

x-2=13

x=15
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Please Carify second question further.

by nbpatel » Thu Nov 13, 2008 6:50 am
I understand how you did the first problem but I really don't follow what you are doing with the second solution can you please clarify....I am Stumped! thanks...and what do you think...would these questions be easy medium or hard?

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Re: Please Carify second question further.

by logitech » Thu Nov 13, 2008 9:43 am
nbpatel wrote:I understand how you did the first problem but I really don't follow what you are doing with the second solution can you please clarify....I am Stumped! thanks...and what do you think...would these questions be easy medium or hard?
what I was trying to do was to have an equation as below:


A^X B^Y = A^Z B^W

So;

When the base numbers are the same, the power needs to be the same:

X=Z

Y=W
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nbpatel wrote:I need help with this question:

2^4 + 2^4 + 3^5 +3^5 + 3^5

They somehow simplified it to tthis answer of 2^6 + 3^6

Also another similar question that I was having trouble with was:

2^(x) - 2^(x-2) = 3(2^13) what is the value of x

They got the answer of: 15`
Can someone further explain how you simplify:
2^4 + 2^4 + 3^5 +3^5 + 3^5 ?

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njbdrexel wrote:
nbpatel wrote:I need help with this question:

2^4 + 2^4 + 3^5 +3^5 + 3^5

They somehow simplified it to tthis answer of 2^6 + 3^6

Also another similar question that I was having trouble with was:

2^(x) - 2^(x-2) = 3(2^13) what is the value of x

They got the answer of: 15`
Can someone further explain how you simplify:
2^4 + 2^4 + 3^5 +3^5 + 3^5 ?
2^4 + 2^4 = 2*(2^4)

3^5 +3^5 + 3^5 = 3*(3^5)

since 2*2^4 = 2^5 and 3*3^5 = 3^6

so it is 2^5 + 3^6


edited: its like saying X+X = 2X and Y+Y+Y = 3Y

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ssmiles08 wrote:
njbdrexel wrote:
nbpatel wrote:I need help with this question:

2^4 + 2^4 + 3^5 +3^5 + 3^5

They somehow simplified it to tthis answer of 2^6 + 3^6

Also another similar question that I was having trouble with was:

2^(x) - 2^(x-2) = 3(2^13) what is the value of x

They got the answer of: 15`
Can someone further explain how you simplify:
2^4 + 2^4 + 3^5 +3^5 + 3^5 ?
2^4 + 2^4 = 2*(2^4)

3^5 +3^5 + 3^5 = 3*(3^5)

since 2*2^4 = 2^5 and 3*3^5 = 3^6

so it is 2^5 + 3^6


edited: its like saying X+X = 2X and Y+Y+Y = 3Y

Perfect! Thank you so much :D