rsl1121 rsl1121
  • 16-04-2015
  • Mathematics
contestada

x+7=2y+1
3x-y=7

solve for x and y

Respuesta :

eu99li
eu99li eu99li
  • 16-04-2015

{x+7=2y+1    ⇔  x-2y=1-7   ⇔ x-2y=-6

{3x-y=7     /*(-2)

{x-2y=-6

{-6x+2y=-14      (+)

x-6x-2y+2y=-6-14

-5x=-20     /:(-5)

x=4

x -2y=-6

4-2y=-6       /-4

-2y=-10     /:(-2)

y=5

Solution: (4; 5)



Answer Link

Otras preguntas

Rachel works a day job and an evening job. She works 77 hours every two weeks. The ratio of the hours she works at her day job to the hours she works at her eve
Contractions when lifting a weight
Solve the system of equations: y = 2x + 1 y = x2 + 2x – 8 A. (0, 1) and (2, 5) B. (–4, 0) and (2, 0) C. (–3, –5) and (3, 7) D. (–3, 5) and (3, 2)
What is the distance between the points (-1,-9) and (4,-2)? Select the best answer from the choices provided.
How do i work out question 4:
-2x+5+(-x)-5=0solve for "x"​
can someone help me?
3 2 ÷ 1 8 Choose the correct use of the rule for this problem. Two-thirds times one-eighth = StartFraction 1 Over 12 EndFraction Three-halves times 8 = 12 Three
What influence did John Locke have on the Declaration of independence
What is the energy of the electron in a helium ion with a charge of +1 in an orbit with a value of n=4?