Question 938106
Given r = 9
{{{4r + 3s = 75}}}
Plug 9 into the equation for r
{{{4*(9) + 3s = 75}}}
{{{36 + 3s = 75}}}
Subtract 36 from both sides.
{{{3s = 39}}}
Divide both sides by 3
{{{highlight(s = 13)}}}