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Plz Help On Equations! (1 Viewer)

k-la

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1) 260 = -15 + (n-1) x 11 find n answer is 26

2) 5.5 squared = 2.4 squared + 1.2 x S find s Answer is 20.4


please somebody show me how you work these out!!!
 

danster

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1) 260 = -15 + (n-1) x 11 find n answer is 26

260 + 15 = (n-1) * 11

275 / 11 = n - 1

25 = n - 1

25 + 1 = n

26 = n
 

k-la

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aha! i was getting tripped up on the first step - did you plus 15 becuase there was a minus in front of it..? and do you always do the opposite of what is in front of the number? cheers ...big help!
 

danster

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Well. When you move it to the other site of the equal sign you reverse the +/- or multiply/divide.

Eg.

1 = S - 5
1 + 5 = S
6 = S

OR

X + 5 = 10
X = 10 - 5
X = 5

OR

A * 2 = 10
A = 10 / 2
A = 5

OR

B / 5 = 3
B = 3 * 5
B = 15

Hope this helps.
 

k-la

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ya thanx!! ur a great help - hey just another quick question when the equation involves a letter (or number) that is squared, u use the square root to find the answer, what happens when the letter ( or number) is cubed - whats the opposite to find the answer?....lol if that all makes sence..

here's an example : 136 = 4/3 x pye x r cubed
 
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danieljarvis

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k-la said:
1) 260 = -15 + (n-1) x 11 find n answer is 26

2) 5.5 squared = 2.4 squared + 1.2 x S find s Answer is 20.4


please somebody show me how you work these out!!!
nobody did number 2??

5.5squared = 2.4 squared + 1.2 s

30.25 = 5.76 + 1.26

30.25 - 5.76 = 1.2s

24.49 = 1.2s

24.49 / 1.2 = s

s = 20.4083333

s = 20.4
 

xlr8-crillz

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k-la said:
ya thanx!! ur a great help - hey just another quick question when the equation involves a letter (or number) that is squared, u use the square root to find the answer, what happens when the letter ( or number) is cubed - whats the opposite to find the answer?....lol if that all makes sence..

here's an example : 136 = 4/3 x pye x r cubed
lol.

u cube root it.
 

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