Question

2a=8 , a+b=2 use the substitution method to solve the linear system

Answer 1

We have
$\left \{ {{2a=8} \atop {a+b=2}} \right.$
First we are taking first equation, and we are solving it
2a=8       /:2 divide both sides by 2
a=4
Now we can backsubstitute a=4
a+b=2
4+b=2         /-4     (subtract 4 both sides)
4+-4+b=2-4
b=-2
The final answer is
$\left \{ {{a=4} \atop {b=-2}} \right.$