Question

NEED HELP!

Every evening Jenna empties her pockets
and puts her change in a jar. At the end
of the week she counts her money. One
week she had 50 coins, all of them dimes
and quarters. When she added them up,
she had a total of $10.25.

Let d = number of dimes and
q = number of quarters.

Answer 1

the equation would be d+q=$10.25

Answer 2

d + q = 50

10d + 25q = 1025

Multiply the first equation by 10. 

10(d + q = 50) --> 10d + 10q = 500

We combine this with the second equation

10d + 25q = 1025 
10d + 10q = 500

--------subtract--------
15q = 525 iff
q = 35

Plug in q = 35 into any of the original equations,

d + q = 50
d + 35 = 50 iff
d = 15

There are 15 dimes, and 35 quarters.