i REALLY need help on writing and solving equations!! PLEASE

[m_o_r_g_a_n]

Directions:
1. write your let statements ( labeling yourn unknown )
2. write a verbal model
3. write an equation ( algebraic model )
4. solve - show ALL steps!!!

Question: Jack has dimes and nickels. He has 20 coins. Jack has a total of $1.40. How much of each coin does he have?

please help me figure out this problem, im in 8th grade honors algebra, and need some help! thank you so much!

xo

morgan

 

[Unco]

G'day, m_o_r_g_a_n!

1. Tell me, what are your unknowns? What are we trying to find the quantity of? Dimes and nickels, right?

That is,
let x be the number of nickels
let y be the number of dimes

2. Verbal model? As in say outloud what's going on? Sure:
"20 coins of dimes and/or nickels total $1.40 in value".

3. The total of dimes and nickels. in quantity, is 20.
Thus x + y = 20.

Each nickel is worth $0.05.*
Each dime is worth $0.10.*
The total value is $1.40.
Thus 0.05x + 0.10y = 1.40

* These are guesses, you'll have to correct me.

4. You have two simultaneous equations:
x + y = 20 (1)
0.05x + 0.10y = 1.40 (2)

So solve by elimination or substitution. Substitution is certainly easier in this case.

ie. Substitute y = 20 - x into (2) and solve for y. Then use this value in one of the equations to solve for x.

Then write what your answer means in terms of the composition of our hero Jack's pocket.

 

[Unco]

You know, if you're going to double-post (in the same forum topic, might I add), the least you could do is use identical subject lines.

 

[m_o_r_g_a_n]

thank you!!! sorry im new, so i didnt know what to do and no one was really answering ... lol thanks for helping me!

 

[stapel]

...if you're going to double-post (in the same forum topic, might I add), the least you could do is use identical subject lines.

i didnt know what to do and no one was really answering

Nobody works here. There is no staff waiting here to provide instant replies. Tutors are volunteers who surf by when they're able. You should expect to wait days for an online reply. Re-posting in less than half an hour is, I'm afraid, slightly unreasonable.

Thank you for your consideration.

Eliz.

 

[happy]

 

[Denis]

HEY, how you doin' happy?

 

[happy]

Doing great, Denis. Thanks! I've made my yearly return just in time for the school year. Now I'm going to sit back and watch the excitement of students posting endless questions. It's very fun for me to watch other people struggle with problems, and knowing that I already completed my degree.

 

[Denis]

Doing great, Denis. Thanks! I've made my yearly return just in time for the school year. Now I'm going to sit back and watch the excitement of students posting endless questions. It's very fun for me to watch other people struggle with problems, and knowing that I already completed my degree.

A "sit back and watch" degree? :lol: