The correct answer is B) 28.2 m
Y = -2x + 4
6x + 3y = 6x + 3(-2x + 4) = 6x - 6x + 12 = 12
⇒ y = -2x + 4 == 6x + 3y = 12 ⇒ invinite solutions: 12
⇒ no solutions -12, -4, 0, 4
Assume you need x liters 10% acid, y liters 80% acid
Then 10%x + 80%y = 65%*70, and x+y = 70
I get: x = 15, y = 55
About 260 kids have blue eyes or prefer blue eyes
90 minutes = 1.5 hour
car will travel 1.5x miles