Question 705761
Set-Up:
Equation 1: {{{L = 2W + 1}}}
Equation 2: {{{P = 2L + 2W}}} (The perimeter of a rectangle
P = 20
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Since equation 1 is already solved for L, plug (2W + 1) into equation 2 for L
Equation 2: {{{P = 2L + 2W}}}
{{{20 = 2*(2W + 1) + 2W}}}
Multiply the 2 through
{{{20 = 4W + 2 + 2W}}}
Combine like terms
{{{20 = 6W + 2}}}
Subtract 2 from both sides
{{{18 = 6W}}}
Divide both sides by 6
{{{highlight(3 = W)}}}
Now plug 3 into equation 1 for W
Equation 1: {{{L = 2W + 1}}}
{{{L = 2*(3) + 1}}}
{{{L = 6 + 1}}}
{{{highlight_green(L = 7)}}}