Answer:
Juanita dissolves 46 g of MgBr2 (molar mass: 184.11 g/mol) in 0.5 kg of distilled water. What is the molality of the solution?
Answer:
see explanation
Step-by-step explanation:
note when x = - 3
(- 3)³ + 2(- 3)² + 4(- 3) + 21 = - 27 + 18 - 12 + 21 = 0
hence x = - 3 is a zero and (x + 3) is a factor and dividing gives
= (x + 3)(x² - x + 7)
For zeros equate to zero
(x + 3)(x² - x + 7) = 0
equate each factor to zero and solve for x
x + 3 = 0 ⇒ x = - 3
x² - x + 7 = 0 ← solve using quadratic formula
x = (1 ±
) / 2 = (1 ± 3i
) / 2
x =
± 
zeros are x = - 3, x =
±
Answer:
2a +2b +4
Step-by-step explanation:
The perimeter is the sum of the lengths of the three sides. If x represents the length of the third side, then ...
(3a +8) +(5a +b) +x = (10a +3b +12)
Subtracting from the equation everything on the left side that is not x, we get ...
x = (10a +3b +12) -(3a +8) -(5a +b)
= a(10 -3 -5) +b(3 -1) +(12 -8)
= 2a +2b +4
The length of the third side is 2a +2b +4.