Math

How do you solve this by linear combinations?

4x+3y=-8
3x-3y=15

  1. 👍
  2. 👎
  3. 👁
  1. L1 : 4x+3y=-8
    L2 : 3x-3y=15

    Do L1+L2--> 7x=7 so x=1
    in L1 4*(1)+3y=-8
    3y=-12
    y=-4

    the couple of solution is(1,-4)

    1. 👍
    2. 👎
  2. How did you get x=1? by pugging it in with the 8 right?

    1. 👍
    2. 👎
  3. No. Add equation 1 (what mk-tintin labels L1) to equation 2, (L2) to obtain
    7x +0y = -8+15
    7x=7
    x=1

    1. 👍
    2. 👎
  4. doing L1+L2-->4x+3x+3y-3y=-8+15
    --->7x=7
    x=1
    do u understand?

    1. 👍
    2. 👎
  5. Oh i was looking at it all wrong alright i understand it a bit better now, doh was plugging in the wrong numbers haha. Sorry.

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. Math

    Lesson 8: Systems of Linear and Quadratic Equations Check my work 1. Solve the system of equations. y = 2x^2 - 3 y = 3x - 1 a. no solution b. (-1/2, 5), (2, -5/2) c. (-1/2, -5/2), (2,5)*** d. (1/2, 5/2), (2, 5) 2.how many real

  2. Algebra 1 Word Problem (Reiny)

    How am I supposed to solve this? "Sandy makes $2 profit on every cup of lemonade that she sells and $1 on every cupcake that she sells. Sandy wants to sell at least 5 cups of lemonade and at least 5 cupcakes per day. She wants to

  3. Algebra 1--Three Word Problems (Reiny or Kuai)

    Can anyone thoroughly explain how to solve these problems as well as how to graph them? 1. Linda works at a pharmacy for $15 an hour. She also baby-sits for $10 an hour. Linda needs to earn at least $90 per week, but she does not

  4. math

    What is the first step in solving the linear system {2x − 3y = 11 {−x + 5y = −9 by the substitution method in the most efficient way? A. Solve the first equation for x. B. Solve the first equation for y. C. Solve the second

  1. MATH *halp*

    Create two different real-world scenarios—one in which you would use permutations and one in which you would use combinations: Include specific details and an explanation about what makes each situation either a combination or

  2. math

    What is the first step in solving the linear system {2x−3y=11 {−x+5y=−9 by the substitution method in the most efficient way? A. Solve the first equation for x. B. Solve the first equation for y. C. Solve the second equation

  3. Algebra I DONT KNOW HOW TO DO 3 VARIABLES

    Solving Linear Equations and Inequalities Solve by eliminating x (this is solving 3 linear equations) then substitute to the other two equation x + y + 5z =2 (1) 4x - 3y + 5z =3 (2) 3x - 2y + 5z=1 (3) my teacher gave me the answer

  4. math matrices repost for answer

    Can somebody show I how to use matrices to solve the following. I want to solve for Tab first. I wiill ask 9n other part later. It given Tad =1200. .285Tab-.428Tac=0 -.428Tab-.285Tac+.384Tad=0 -0.857Tab-.857Tac+.923Tad=0 Anonymous

  1. Math

    The model builder has 4 pieces of balsa wood that are 4 cm,5 cm, 6 cm, and 7 cm in length. How many different combinations of 3 pieces can be used to make triangles without breaking or cutting the pieces? List the combinations as

  2. MATH

    Let f(x) = m1x + b1 and g(x) = m2x + b2 be two linear functions. Answer the following, noting that answers may depend on the the ms and bs. a. Is f (x) + g(x) a linear function of x? b. Is f (x) − g(x) a linear function of x? c.

  3. Algebra 2

    Solve using linear combinations. x - 5y = 6 3x + 4y = 18 What are linear combinations?

  4. algebra-math

    When it comes to linear inequalities, these are explained to be similar to a linear equation, but the difference between the two is that the equal signs are replaced with an inequality symbol. It is also explained that when it

You can view more similar questions or ask a new question.