Awoman has 21 total coins in her pocket, all of which are either dimes or quarters. if the total value of her change is $3.90, how many dimes and how many quarters does she have? write the number of dimes, then the number of quarters separated by a comma.

Step-by-step explanation:

Givens

With this information we can construct a system of equations, where is dimes and is quarters.

, because there are 21 coins between dimes and quarters.

Now, we know that one dime values 10 cents, and one quarter values 25 cents.

, because the woman has $3.90 in total.

Then, we isolate in the first expression

And we substitute it in the second expression

Then, we use this value to find the other one

Therefore, the woman has 12 quarters and 9 dimes.

answer: 2 answers

step-by-step explanation: the first one means to spread the product throughout the marketplace such that a large number of people can buy it.  

the second means the process of making a product or service available for the consumer or business user that needs it.

mark this brainliest and i will be glad to .

ca = ec

cpctc makes it so that corresponding parts of the triangle you proved to be equal are equal, the other options aren't part of the part of the triangles you proved to be equal.