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Last option: (50, 30); 50 adult tickets and 30 child tickets
What is Linear Equation?
A linear equation is an equation in which the highest power of the variable is always 1.
We have the system of equations:
x + y = 80
6x + 4y = 420
We will use elimination method to solve it:
Multiply the first equation by -6 and then add the equations:
- 6x - 6y = -480
6x + 4y = 420
We get:
-2y = -60
After dividing both sides by -2 we get:
y = 30
then plugging 30 in place of y into the original first equation we get:
x+30=80
Then subtracting 30 from both sides we get:
x = 50
The solution to the system is (50, 30)
Then notice the second equation 6x+4y=420 clear indicates that x represents the tickets for adults since the price for adults $6 is the coefficient of the x-term, while the price for children which is $4 is attached as coefficient in front of the y.
Thus, x=50 means there were sold 50 adult tickets. And y=30 that there were sold 30 child tickets.
Learn more about Linear equation from:
https://brainly.com/question/2263981
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