math

how do i solve this using substitution?

5x+y=15
4x+4y=12

  1. 👍 0
  2. 👎 0
  3. 👁 133
  1. y = 15-5x

    replace y into the other eq

    4x+4(15-5x) = 12

    4x + 60 - 20x = 12
    -16x = -48

    x = 3

    plug 3 onto the fisrt or second eq to get Y..

    y = 15-5x
    y = 15-5(3)

    y = 0

    1. 👍 0
    2. 👎 0

Respond to this Question

First Name

Your Response

Similar Questions

  1. Algebra PLEASE HELP!!

    What advantages does the method of substitution have over graphing for solving systems of equations? Choose the correct answer below. A. Graphing cannot be used to solve dependent or inconsistent systems due to the nature of the

  2. Algebra 2

    Solve by Substitution x + 2y + z = 14 y = z + 1 x = -3z + 6

  3. How do I do this.?(Math.)

    Use the Substitution method to solve the system of equations. y - 2x = -5 3y - x = 5 Solve one of the equations for x or y. Let's solve the first one for y: y - 2x = -5 y = 2x - 5 Now let's substitute 2x - 5 for y in the second

  4. Algebra

    Solve the system of equations using substitution. x + 4y = -5 3x - 8y = 45 When I tried to solve it, I got x=-17 and y=-3. When I plugged these into the first equation, it didn't work out at all. Could someone please show me the

  1. math

    Solve systems by substitution 5x - 2y = -5 y - 5x = 3 Substitute 5x + 3 for y in the first equation, and solve it for x. Once you have x, use either of the two equations you wrote to solve for y.

  2. Algebra 2

    Solve by substitution -7x + y=1 7x- 6y =-6

  3. algebra 2

    4p + 2q = 8 and q = 2p +1 solve by substitution

  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. 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

  2. Algebra

    Solve using substitution 5x-2y= 0 and 3x=y =-1

  3. Linear Equations

    Can you please help solve this equation using the substitution method? I have tried and keep getting that X and Y = 7/2, but the answer in the book states no solution, inconsistent system. What am I doing wrong? Please help! Solve

  4. Algebra help!

    1.) Solve the system by triangularizing the augmented matrix and using back substitution. -x-y+z=1 x-y-4z=-7 4x+y+z=6 2.) Perform the indicated row operation, then write the new matrix. -4 4 | 4 9 -6 | 5 -2R1+ R2 ---> R2 3.) Solve

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