Answer:
11) A
12) B
Explanation:
11) 10x² + 1 = 0
Subtract 1 from both sides:
10x² = -1
Divide both sides by 10:
x² = -1/10
Take the square root of both sides:
x = ±√(-1) / √(10)
Remember that the square root of -1 is i:
x = ±i / √(10)
To rationalize the denominator, multiply top and bottom by √10.
x = ±i√(10) / 10
Answer is A.
12) 2v² + 8v + 6 = 0
Divide both sides by 2:
v² + 4v + 3 = 0
Use AC method or quadratic formula to factor:
(v + 1) (v + 3) = 0
Set each expression to 0:
v + 1 = 0 or v + 3 = 0
Solve:
v = -1 or v = -3
Answer is B.