Solve the system by the addition method

-10x^2 + 10y^2-320=0
30x^2 + 6y^2 - 336 = 0

  1. 👍 0
  2. 👎 0
  3. 👁 75
asked by LT
  1. multiply the first by 3
    -30x^2 + 30y^2 = 960
    30x^2 + 6y^2 = 336, add them
    36y^2 = 1296
    y^2 = 36
    y =±6

    plug y = 6 into one of the equations and find the x
    do the same with y = -6

    1. 👍 0
    2. 👎 0
    posted by Reiny

Respond to this Question

First Name

Your Response

Similar Questions

  1. 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

    asked by jessica on May 9, 2007
  2. Algebra 2

    "My husband's age," remarked a lady the other day, "is represented by the figures of my own age reversed. He is my senior, and the difference between our ages is one-eleventh of their sum." 10x + y = husband's age 10y + x = wife's

    asked by Anonymous on October 25, 2011
  3. Algebra

    A certain number is three times the sum of its digits,if 45 is added to the digit it is reverse. Find the digit. Let the two digit number be xy(10x and y) xy=3(10x+y) 3(10x+y)+45=10y+x how to solve this sum in addition and

    asked by Nathya on November 14, 2015
  4. Math

    Solve using the elimination method. Show your work. If the system has no solution or an infinite number of solutions, state this. 10x + 5y = 52.5 30x – 7y = 80.5

    asked by Shirley on February 5, 2012
  5. Operating research

    Use simplex method to solve Maximize p = 30x + 20y+30z subject to x + y+z

    asked by Terry on June 17, 2011
  6. operation research 1

    Use simplex method to solve Maximize p = 30x + 20y+30z subject to x + y+z

    asked by mashoo on June 17, 2011
  7. math

    solve using any appropriate method 10x+y=278 10y+x=107

    asked by Keya on August 10, 2014
  8. Intermediate Algebra

    Determine whether the point (1, 8) is a solution of the system 2x + 6y = 50 10x + 0y = 10 by substituting the point into each equation. So far I have: 2x=6y=50 y=50-2x 10x+10y=10 10x+0(50-2x)=10 10x+0=10 x=10 y=50-2x y=50-2(1)

    asked by Jordan on October 7, 2010
  9. 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"

    asked by Gail on March 24, 2009
  10. Algebra 1

    Solve each of the following system by addition. If a unique solution does not exist,state whether the system is inconsistent or dependent. equation is like this x+5y=10 -2x-10y=-20

    asked by Candy on September 3, 2007

More Similar Questions