Acollection of nickels and dimes is worth $9.45. if the number of dimes is doubled, the value is
$16.65. find the number of each coin using substitution.

The number of nickels is 45 and the number of dimes is 72.

Step-by-step explanation:

Let

x ----> number of nickels

y ----> number of dimes

Remember that

so

------> equation A

------> equation B

Solve the system by substitution

we have

------> equation A

------> equation B

Multiply both equations by 100 both sides

----> --> equation C

----> equation D

substitute equation C in equation D

solve for y

Find the value of x

Alternative Method

Solve the system by graphing

Remember that the solution is the intersection point both graphs

using a graphing tool

the solution is the point (45,72)

therefore

The number of nickels is 45 and the number of dimes is 72.

answer: all of the odd numbers were opened

the first person was the one that was opening all of the lockers. since one is odd, this causes all of the odd number lockers to be opened in the end.

42

step-by-step explanation: