Peggy had three times as many quarters as nickels. She had $1.60 in all. How many nickels and how many quarters did she have?

0.05n + 0.25q = 1.60

q = 3n

0.05n + 0.25(3n) = 160

0.05n + 0.75n = 1.60...multiply by 100 to get rid of the decimals

5n + 75n = 160...answer D

Step-by-step explanation:

(meow) <3

  or  

step-by-step explanation:

if the four friends split the cost, p, of the pizza evenly, then each friend pays one-fourth of the cost of the pizza.

the expression is   or  

option (b) is correct

step-by-step explanation:

to find the solution of this system, we need to convert it into reduced row-echelon form. we have,

after applying row operations r2 -> r2/2 and r3 -> r3/3, we get,