Question 84500
Solve by substition:
{{{x+y = 12}}}
{{{y = 2x}}} Substitute this value of y into the first equation and solve for x.
{{{x+2x = 12}}} Combine like-terms.
{{{3x = 12}}} Divide both sides by 3.
{{{x = 4}}} Now substitute this value of x into the second equation and solve for y.
{{{y = 2(4)}}}
{{{y = 8}}}
The solution is: (4, 8)
You can also see this when you graph these two linear equations.
The solution is the point of intersection of the two lines.
{{{graph(300,200,-3,6,-2,16,-x+12,2x)}}}