Answer:
x = 72 / 85
Step-by-step explanation:
x -6/7=-x/84
x + x/84 = 6/7
84/84x + 1/84x = (12*6) / (12*7)
85/84x = ( 72 ) / ( 84 )
85/84x = 72 / 84
Multiply left and right from the = sign by 84/85 and you do that so you get a division ON THE LEFT SIDE that equals as 1... See how it works:
84/85 * { 85/84 } * x = 84/85 * { ( 72 ) / ( 84 ) }
{ (84 * 85) / ( 85 * 84) } * x = ( 84 * 72 ) / ( 85 * 84 )
(7140) / ( 7140) * x =. ( 6048 ) / ( 7140)
x = 6048 / 7140
x = 72 / 85
How they dress, What movie they buy, and what snacks you buy
<h3>
Answer: </h3><h3>
There are 75 coins that aren't nickels. </h3><h3>
One equation you could use is 75+n = 92</h3>
(This solves to n = 17 meaning there are 17 nickels)
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Explanation:
"There are 25 pennies, 21 dimes, and 29 quarters", so there are 25+21+29 = 75 coins so far. This is the amount of coins that aren't nickels. The rest are nickels, which is some amount n. This adds to the 75 to get 75+n. Set this equal to 92 because there are 92 coins in all. That's how we end up with 75+n = 92.
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Extra info
The equation 75+n = 92 is the same as n+75 = 92. Subtract 75 from both sides to isolate n. You should get n = 17 after doing so.