Answer:
Let tacos be x and enchiladas be y
6 tacos + 4 enchiladas = 52
becomes
6x+4y=52
^^that's our first equation
Now, the second equation
7 tacos + 9 enchiladas = 78
7x+9y = 78
^^^that's our second equation
Isolate y in the first equation:
6x+4y=52
4y=52-6x
y = (52-6x)/4
^^^Let's call this equation 3
Now, sub-in equation 3 into equation 2
*replace the y*
Equation 2: 7x+9y = 78
Sub-in
7x+ <u>9 ( (52-6x)/4)</u> = 78
Do some algebra (get your x terms on one side) and you will find your x value
7x + <u>117 - 13.5x</u> = 78
(7x-13.5x) = 78-117 *get your x terms on one side
x=6
That's the cost of one taco.
Now, find y. Pick an equation (1,2 or 3). Let's pick 3 since y is already isolated.
All you do is plug in your x value.
Equation 3: y = (52-6x)/4
y= (52 -6(6))/4
...
You should be able to solve this on your own
Step-by-step explanation:
:)) You can solve for y now
