Let
x-----------> cost of one hamburger
y-----------> cost of one <span>order of fries
we know that
4x+2y=9.74--------------> equation 1
12x+y=22.77-----------> y=22.77-12x-----------> equation 2
using a graph tool---------> calculate the equations system
see the attached figure
</span><span>
the solution is
x=1.79
y=1.29
the </span>cost of one hamburger is $1.79
the cost of one orders of fries is $1.29
<span>If Tashiana buys 3 hamburgers and one order of fries
3*1.79+1.29---------> $6.66
the answer is $6.66</span>