You can put this solution on YOUR website! Ax+By=C [Use the standard form of a line to solve]
$5.00 x + $10.00y=$100
and
x+y=12
So, x+(12-x)=12
.
5x+10(12-x)=100
5x+120-10x=100 [solve for x]
-5x=100-120
-5x=-20
x=4
y=(12-x)=12-4=8 [solve for y]
.
Checking:
$5.00 (4) + $10.00(8)=$100
$20 + $80 = $100
$100=$100
and checking:
x+y=12
4+8=12
12=12