Question

How do you solve the system a+b=11 and 3a-2b=8?

Answer 1

`(a,b)to(6,5)`

Explanation:

`a+b=11to(1)`

`3a-2b=8to(2)`

`"from equation "(1)color(white)(x)a=11-bto(3)`

`"substitute "a=11-b" into equation "(2)`

`3(11-b)-2b=8`

`33-3b-2b=8`

`33-5b=8`

`"subtract 33 from both sides"`

`-5b=8-33=-25`

`"divide both sides by "-5`

`b=(-25)/(-5)=5`

`"substitute "b=5" into equation "(3)`

`a=11-5=6`

`"solution is "(a,b)to(6,5)`