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the surface area ?


ikhlas

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Please guys any help here and as usual with detailed answer , if you may

 

1 ) How many cubes, each having a surface area of 54 sq in , will fit exactly inside a larger cube having a surface area of 216 sq in ??

The answer is 8 ?

The surface area cube is 6*(x 2 ) , but I think we didn't need to do this ??

And any q ask us how many cub means volume ? am right ?

By the way what is the surface area for cylinder , I think the same = pi * r2 *h , but my q is the surface area for cylinder is the same as the area for cylinder ??

We have two cercal??

2) If we have line which intercept in ( 5,0,) and in (0 , 3 ) , ( please imagine that ) , which is the following equations describes the line drawn for this line ?

The answer is y = -1/2x + 2 , how we can know that ?? just pick any sopt or it must from the q ?? i hope you understand me guys ??

ikhlas

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2) If we have line which intercept in ( 5,0,) and in (0 , 3 ) , ( please imagine that ) , which is the following equations describes the line drawn for this line ?

The answer is y = -1/2x + 2 , how we can know that ?? just pick any sopt or it must from the q ?? i hope you understand me guys ??

 

 

ikhlas

 

the general form of a line is

y = ax + b

a and b are coefficients and can be calculated

although the substitution approach by gstergia works it may be slow if you have to substitute in a number of equations. The good news is that there is an alternative approach.

the b in the formula above (oooops, looks like there is a mistake somewhere) represents the y-intercept when x=0 and in this problem b = 3

the a is the slope of the line which is rise/run = (y2 - y1)/(x2 - x1) and in this case is (0-3)/(5-0) = -3/5

so the equation must look like

y = -3/5x + 3

check the answer

I dont have time to go into more details but will elaborate if needed

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Hi metodive

thanks for your helping .

the b in the formula above (oooops, looks like there is a mistake somewhere) represents the y-intercept when x=0 and in this problem b = 3

the a is the slope of the line which is rise/run = (y2 - y1)/(x2 - x1) and in this case is (0-3)/(5-0) = -3/5

so the equation must look like

y = -3/5x + 3

check the answer

I dont have time to go into more details but will elaborate if neededi am sure ,

i get the same answer ,and i pluge how can i get this formula ??

ok if you want i will put the other choices .

y = 2 x -1

y = x + 2

y = 1/2x + 2

y = 2

y = -1/2x +2 and my book say this is the answe ?!!but no details

thanks

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thanks gstergia !!

 

1.a

yes :D
.

please tell me how you get this answer ?? ( 8 how ??!! )

there is answer by S3 = S2 * S ,, ITHINK THIS IS NOT AS WE KENWO ??

 

2 if you plug in y=0 then you should get x=5 and if you plug in y=3 you should get x=0. Yuo want the equation that has the above properties. :D

 

thanks

ikhlas

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