Let 
be the amount of the 30% alloy and 
the amount of the 60% alloy the metalworker will use. However much is used, the final alloy will have a mass of
kilograms. For each kg of the 30% alloy used, 0.3 kg is copper; similary, each kg of the 60% alloy contributes 0.6 kg, so that
Now,
Answer:give me brainlist
Step-by-step explanation:
For number 19:
"at least 150" means either 150 ≤ ? or ? ≥ 150
plus 3 so +3x
The answer would be 150 ≤ 100 + 3x
Number 20:
A is at -2.5. The inverse is the opposite so 2.5
Answer:
D
Step-by-step explanation:
because 
is radical
