Answer:
Number 1 and Number 4
Step-by-step explanation:
By factoring, you can figure out the roots (x = -2 or x = 2)...
1. x^2 - 4 = 0
--> (x + 2)(x - 2) = 0
--> x = -2, x = 2
2. x^2 + 4 = 0
--> factors weirdly, so I won't write it. You'd have to use the quadratic formula.
3. 3x^2 + 12 = 0
--> 3 (x^2 + 4) = 0
--> factors weirdly (same as above)
4. 4x^2 - 16 = 0
--> 4 (x^2 - 4) = 0
--> 4 (x+2) (x-2) = 0
--> x = -2, x = 2
5. 2 (x-2) 2 = 0
--> x = 2
I LOVE THIS PUZZLE
so,
the solution is
take 10 coins off to the side
flip those 10 over
done
sounds too simple?
this can be solved with algebra for ANY number of coins
lets say we have 50 coins, all tails
we flip h coins head
if h=x+y
if we seperate h coins off, we get x heads, and y tails
and in the other pile, we have y heads and the rest of the tails
so now, if we flip all the coins, we get y heads in the pile and x tails
solution:
seperate 10 coins and flip all 10 of them over
Answer:
Answer is D. 1572 square units.
I’m think the answer is 28