The variable x always equals 1
16x + 21y = 555
Step-by-step explanation:
Let x be the no. of 18-hole course
And y be the no. of golf balls
16x + 21y = 555
X-y=2 (*-2) --> -2x+2y=-4
2x+3y=14
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2x+3y=14
-2x+2y=-4
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5y=10
y=2
35+5(4-s)=2550
35+20-5s=2550
55-5s=2550
-55 -55
-5s = 2495
s = - 499
-499 + a = 4
+499 +499
a = 503