Question

Is anyone willing to help me with 8 out of 50 questions? Please? Comment if you will, then I'll post one at a time.

Answer 1

That's a big order, Florida girl. Why not post one at a time? You'd probably get more responses that way.

Answer 2

Okay.. Thanks. Its only 8 questions I am not sure about or don't understand. Thanks though. @mathmale

Answer 3

I wasn't trying to dismiss you. On the contrary, I was inviting you to post a question so that we could get started discussing it.

Answer 4

oh! Here is the first 1.
A system of equations is shown below.

4x = - 3y + 17
3x - 4y = - 6

What is the solution to this system of equations?

(-2, -3)

(3, 2)

(2, 3)

(-3, -2)

Answer 5

@mathmale

Answer 6

4x = - 3y + 17
3x - 4y = - 6

Which method of solving systems of linear equations is most familiar to you? substitution? addition/subtraction? graphing? We'll go with whichever method you choose.

Answer 7

the substitution method is what I am most familiar with. Lets use that one. @mathmale

Answer 8

Fine. Take a look at the first equation. 4x=-3y+17. Solve for x by dividing every term by 4. would you do that, please? When you're done, we'll substitute this expression for x into the second equation.

Answer 9

Okay, divided every term by 4.
4x=-3y+17
x= -.75y+4.25
Is this correct? @mathmale

Answer 10

Looks great! Now please substitute -.75y+4.25 for x in the second equation. Solve for y.

Answer 11

3x-4y=-6
3(-.75+4.25)-4y=-6
-2.25+12.75-4y=-6
10.50-4y=-6
-4y=-16.50
y= -4.125
Is this all correct?

Answer 12

@mathmale

Answer 13

Just about perfect! Congrats! But take a second look at -4y=-16.50. Divide both sides by -1. What do you get?
How would you now find x?
How would you check your final result?

Answer 14

Okay.. I divided both sides by -1.
4x= 16.50
Then I would divide 4? Which would be x=4.125
I would fill x in for 4.125, right?
@mathmale

Answer 15

Actually, that'd be y=4.125, same as your original answer, except for sign.

Answer 16

Florida: You're on the right track. Really. But I note that our y does not match any of the given answers, which means that somewhere along the line we have an arithmetic error. I will work through this quickly and see whether I can find it.

If you're familiar with the addition/subtraction (elimination) method, why not try that in the meantime?

In other words, solve the system 4x+3y=17 3x-4y=-6.

Answer 17

Florida: I was able to solve the system of equations by substitution; I got y=3.

Solving 4x = - 3y + 17 for x, I got x=(-3y+17)/4. I chose NOT to convert that to decimal fractions.

I then substituted this expression for x into the second equation and got the following:
\[3\left( \frac{ -3y+17 }{ 4 } \right)-4y=-6.\]

Answer 18

Multiply every term by 4 to eliminate fractions. Solve the resulting equation for y.

I'm so sorry, but I need to get off the computer pretty quickly. I encourage you to post your other questions too. If you're not in a hurry, I'd work with you again much later today or sometime tomorrow, but urge you not to wait for me. Good luck!

Answer 19

okay, I asked my dad, since he just got home and he has walked me through it, my answer is (2,3)