Algebra

posted by .

8s+ 12 = 16, 6s+ 9t = 12 solve by substitution

  • Algebra -

    I think you have a typo and you should have 12t in the first equation
    If so, then drwls made the following observation

    http://www.jiskha.com/display.cgi?id=1282324238

  • Algebra -

    8s+12=16............. equation 1
    6s+9t=12............. equation 2

    Multiply equation 1 by 3 and equation 2 by 4 and subtract.

    +24s+36= +48
    +24s+36t=+48
    - - - (sign will change when sub)
    .............
    36-36t=0
    t=1
    put t=1 in equation 2
    6s+9(1)=12
    s=1/2

    CHECK 6(1/2)+9(1)=12
    12=12
    LHS=RHS so your answer is correct

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  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 it.How …
  2. algebra 1

    Solve the Foll by substitution x=1/5y 3x+2y=26 So, substitute 1/5y for x in the second equation. Then solve for y. Can you take it from here?
  3. Algebra

    Can someone please help solve this? Solve by using addition or substitution or addition. 10x+2y=7 y=-5x+3 the answer my got was x=11/10 y=-2 My teacher said that was wrong. Never mind this post I found out how to solve it. Try substitution.
  4. math

    solve each system of equations by substitution. y=3x-9 please help explain how to solve this using substitution.
  5. substitution method

    Solve by substitution method please help me solve this. I do not know how to do this at all. The question is 3x+8y=33 and x=31-6y I know that I have to plug x into the first x like 3(31-6y)+ 8y = 33 but i do not know what to do from …
  6. algebra

    i need help with these problems (either a solution or how to plug them into a graphing calculator): 1) Solve by substitution or elimination 4/x + 1/y + 2/z = 4 2/x + 3/y - 1/z = 1 1/x + 1/y + 1/z = 4 2)Solve the system of equations …
  7. Algebra 1

    bobpursey, In this problem you helped me with earlier: Solve using any appropriate method. y = 2× - 5, y = ½× + 1 Substitution, substitute for y. 2×-5=½ × + 1 3/2 x=6 x=4 y= 2*4-5=3 How did you choose which method you were going …
  8. Math

    17) solve this linear system using the method of substitution. 2y-x=-10 y= -3/2x-1 20) simplify then solve by substitution 2(x-4)+y=6 3x-2(y-3)=13 just need help with these 2.
  9. Algebra

    I need help learning to solve substitution. I have a problem that says solve the system by substitution -4.5x-2y=-12.5 3.25x-y=-0.75
  10. Algebra PLEASE HELP!!

    What advantages does the method of substitution have over graphing for solving systems of equations?

More Similar Questions