Question

Dory and Nemo go to Taco Bell for lunch. Dory orders three soft tacos and three double deckers for $11.25. Nemo pays $10.00 for four soft tacos and two Double Deckers. Write a system of equations that represents the lunch orders for Dory and Nemo. Use x to represent soft tacos and y to represent Double Deckers.

Answer 1

Answer: The cost of soft tacos is $1.25 and the cost of Double deckers is $2.5.

Step-by-step explanation:

Let the cost of soft tacos be 'x'.

Let the cost of double deckers be 'y'.

According to question,

$3x+3y=\ 11.25\\\\x+y=\frac{11.25}{3}=3.75-----------(1)\\\\4x+2y=\ 10\\\\2x+y=\ 5-----(2)$

From eq(1), we can get that

$y=3.75-x$

Put it in the equation(2), we get

$2x+y=\ 5\\\\2x+3.75-x=\ 5\\\\x=\ 5-\ 3.75\\\\x=\ 1.25$

And put the value of x in $y=3.75-x=3.75-1.25=\ 2.5$

Hence, the cost of soft tacos is $1.25 and the cost of Double deckers is $2.5.

Answer 2

X=cost for 1 soft taco
x=cost for 1 doubledecker

dory is
11.25=3x+3y

nemo buys
10=4x+2y

we have
11.25=3x+3y and
10=4x+2y
divide second equation by 2
5=2x+y
multiply by -3
-15=-6x-3y
add to first equatin

-15=-6x-3y
11.25=3x+3y+
-3.75=-3x+0y

-3.75=-3x
divide both sides by -3
1.25=x
subsitute

5=2x+y
5=2(1.25)+y
5=2.5+y
minus 2.5
2.5=y


double dekesr cost $2.50
soft tacos cost $1.25