So here you're using system of equations. You can solve systems by graphing, elimination, or substitution. Ill use substitution. First lets solve for x. take the second equation and add y to both sides to get x by itself:
x - y = 75
x = y + 75 now plug y+75 in for x in the first equation
x + y = 743
(y +75) +y = 743 solve for y
2y +75 = 743 subtract 75
2y = 668 divide both sides by 2
y = 334
now plug this into any of the 2 equations to solve for x i chose the second one
x - y = 75
x - 334 = 75 add 334 to both sides
x = 409
This means x, sold before the tournament is 409 and y, sold at the door is 334. That means the assistant is wrong and accidentally flipped the two answers
The drawing will explain all that you need yo answer this question. Note, you do have to use Pythagorean theorem. You can do what I drew because of a theorem that states if a segment is perpendicular to a chord then that segment bisects the chord.
Answer:
Y int = 4
x int = 6
Step-by-step explanation:
In the 3rd row where it says "3x(x-3)(x+3)", it should be "3x(x+3)(x+3)" and the solutions should be -3,-3,0