DanH-Algebra 1

posted by .

Solve the system of equations using the Addition method.

2a + 3b = -1
3a + 5b = -2


Margie:
Roger's answer below is correct. If you don't understand it, please try and tell us what you don't understand.


He makes it sound so strange can you ask him to explain in an easier way?


What Roger showed you is this:

When you have 2 equations with 2 "unknowns" (in this case, a and b are unknowns), you have to make one of the unknowns go away. So, you have to figure out how to make one of the unkowns go away. Let's pick the a. How do you make the a's go away? If you add the 2 equations together, you see that the a's don't go away, it leaves you with 5a. If you subtract the bottom equation from the top, you see that the e's still don't go away, because that leaves you with -a. So, the only way to make the a's go away is to multiply the top equation by -3, and the bottom equation by 2. When you do this, you get -6a in the top equation, and 6a in the bottom. Then, when you add the equations together, the a's go away! Now you're just left with the b's to deal with.
Does this make sense??


YES!!!Thank you,you make sense.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Algebra 2345678!!

    Solve the system of equations using the Addition method. 2a + 3b = -1 3a + 5b = -2 The addition method tells you to find common multiples of a coefficient, then add the equations together to eliminate a variable. If you multiply the …
  2. Substitution Method-Plz help

    Use the Substitution method to solve the system of equations. x + y = -4 x - y = 2 solve for x in the second equation. x= y+2 Put that in for x in the first equation: x+y=-4 (y+2) + y = -4 solve for y. Then, x= y+2 i don't get it.How …
  3. Algebra - solving linear equations w/ substitution

    The question in the book reads: "Suppose you try to solve a system of linear equations using substitution and get this result. How many solutions does each system have?
  4. Algebra

    Checking a few answers to some algebra problems: 1.Find the slope of the line that passes through the points (-4,1) and (3,5). I got m = 5-1 / 3-(4) Answer is m = 4/7 2.Find the equation, in slope-intercept form, of the line that passes …
  5. algebra

    Solve the system of equations using the addition (elimination) method. If the answer is a unique solution, present it as an ordered pair: (x, y). If not, specify whether the answer is "no solution" or "infinitely many solutions" and …
  6. Linear Equations

    Can you please help solve this equation using the substitution method?
  7. Math

    solve the system of linear equations using the addition method. Can you please show me the steps on how you reached the answer. Thank You 2x+20y= -144 12x+5y= 56
  8. Algerbra

    Q1. Solve the system of equationd by addition method. -2x+y=6 -3x-4y=20 Select the correct choice below and, if necessary, fill in the answer box to comlete your choice a)The solution is__(simplify your answer. type an ordere pair) …
  9. Algebra

    Solve the following systems of equations using the addition (elimination) method. What type of system is it?
  10. Pre-Calc

    Solve the system of equations using either the substitution method or the multiplication/addition method answer: 3x+2y=14 2x-4y=4

More Similar Questions