Answer:
A single taco costs $1.31
A single quesadilla costs $2.89
Explanation:
Let's suppose that:
T is the price of a single taco.
Q is the price of a single quesadilla.
Thelma ordered 2 tacos and 1 quesadilla, and she paid $5.51, this can be written as:
2*T + 1*Q = $5.51
And we know that Louise ordered 2 quesadillas and 1 taco, and she paid $7.09, this can be written as:
1*T + 2*Q = $7.09
Then we have a system of equations:
2*T + Q = $5.51
T + 2*Q = $7.09
To solve this, we first need to isolate one of the variables, let's isolate T in the second equation:
T = $7.09 - 2*Q
Now we can replace this in the first equation:
2*($7.09 - 2*Q) + Q = $5.51
Now we can solve this for Q.
2*$7.09 - 2*(2*Q) + Q = $5.51
$14.18 - 4*Q + Q = $5.51
$14.18 - 3*Q = $5.51
$14.18 - $5.51 = 3*Q
$8.67 = 3*Q
($8.67)/3 = Q
$2.89 = Q
This means that the price of a single quesadilla is $2.89
Now we can use the equation:
T + 2*Q = $7.09
T + 2*($2.89) = $7.09
T + $5.78 = $7.09
T = $7.09 - $5.78 = $1.31
The price of a single taco is $1.31