Cathlean:
3 tacos
3 burritos
total : $11.25
t = cost of a taco
b= cost of a burrito
3t + 3b = 11.25
Tina
4 tacos
2 burritos
total : $10
4t + 2b = 10
A. System of equations:
3t + 3b = 11.25
4t + 2b = 10
B.
Solve the first equation for t
3t= 11.25-3b
t= (11.25-3b)/3
t= 3.75-b
substitute t in the second equation, and solve for b
4 (3.75-b) + 2b = 10
15-4b+2b =10
-4b+2b=10-15
-2b= -5
b=-5/-2
b=2.5
Subtitute b in the first equation and solve for t
3t +3 (2.5)=11.25
3t+7.5=11.25
3t= 11.25-7.5
3t= 3.75
t=3.75/3
t= 1.25
c.
If each taco costs $2 , replace t by 2 in each equation and solve
Cathlean:
3t + 3b=
3(2)+3(2.5) =
6+7.5 = $13.5
Tina
4t + 2b =
4(2)+2(2.5) =
8+5 = $13