Question 278369
a+b+c=45
a=2b
c=5+b
substitute and solve for b, then a and c.
{{{2b+b+5+b=45}}} add
{{{4b+5=45}}} subtract
{{{4b=40}}} divide
{{{highlight(b=10)}}} second
a=2b
{{{a=2(10)}}}
{{{highlight(a=20)}}} first
c=5+b
{{{c=5+(10)}}}
{{{highlight(c=15)}}} third