n + q = 58

5n + 25q = 770

5n + 5q = 290

20q = 480

q = 24, n = 34

The jar has 34 nickel coins and 24 quarter coins.

"A jar containing 58 ​coins are either quarters or nickels"

q+n = 58

n = 58-q

"The total value of the coins is ​$7.70"

0.25q + 0.05n = 7.70]

substitution

0.25q + 0.05(58-q) = 7.70

0.25q + 2.90 - 0.05q = 7.70

q = 24

n = 58-q = 82

25q + 5(58 - q) = 770

20q = 770 - 290 = 480

q = 24, n = 34

58-N=number of quarters

N=number of nickels

(58-N)0.25 + N(0.05) = 7.70

14.5-0.25N + 0.05N = 7.70

14.5 -0.20N = 7.70

14.5-7.70 - 0.20N = 7.70-7.70

6.80 -0.20 N + 0.20 N = 0 +0.20N

6.80 = 0.20N

6.80/0.20 = 0.20N/0.20

34 = N

58-N= 58-34 = 24

34 nickels

24 quarters

A jar containing 58 ​coins are either quarters or nickels The total value of the coins is ​$7.70 How many of each type of coin do they​ have?

let x = # of quarters

then, 58 - x = # of nickels

value of coins:

25x + 5(58 - x) = 770

solve for x...SIMPLE, right ?!

20x = 770 - 290 = 480

x = 24

there are 24 quarters and 34 nickels...check...do SOMETHING !!

Google it.