ilene2005
ilene2005 ilene2005
  • 19-10-2018
  • Mathematics
contestada

Can someone explain me the equations on #3??!

Can someone explain me the equations on 3 class=

Respuesta :

OmegaAzzy
OmegaAzzy OmegaAzzy
  • 19-10-2018

Sally's age is 3.

Tomas's age is 6.

x + 2y = 12

x - y = 3


Add y to both sides of the second equation.

x = 3 + y

Plug this equation into the first equation.

3 + y + 2y = 12

Combine like terms.

3 + 3y = 12

Subtract 3 from both sides.

3y = 9

Divide both sides by 3.

y = 3

Now that we have the value of y, we can find the exact value of x.

Plug this value into the second equation.

x - 3 = 3

Add 3 to both sides.

x = 6

We can verify by plugging these values into either equation.

6 + 2(3) = 12

6 + 6 = 12

12 = 12

The values are correct.


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