He would have to take out at least 16 coins.
Taking any less could result in having fewer quarters since even 15 could result in <span>12 dimes and 3 quarters. This way it will always be at least 4 quarters.</span>
Step-by-step explanation:

Combine like terms on left hand side. Like terms are those which have the same base. Only coefficients of like terms can be added or subtracted.
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Transpose 2x to left hand side and change it's sign.
Similarly , Transpose 10 to right hand side and change it's sign.
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Divide both sides by 6
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Hope I helped ! ♡
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Answer:
D : [-2,0) U (0, infinity) ; -2<=x<0 U x>0


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13/2170 = 0.006 (to 3 decimal places)
Answer:
For the 1st question (4) For the 2nd question (1)
Step-by-step explanation:
(4) because 15000x+10000y needs to be less than or equal to 20000 or else they're going over the budget but x+y needs to be less than or equal to 15 as they can't make more than that.
(1) Divide both sides by pi and h then square root both sides.