Answer:
A
Step-by-step explanation:
Given
x² - 16x + 64 = 0 ← left side is a perfect square and factors as
(x - 8)² = 0, thus
x - 8 = 0 ⇒ x = 8 with multiplicity 2
Thus x = 8 is the only solution → A
Answer:
d) 2x(4x + 2)
Step-by-step explanation:
a) 4(2x + 1) = 8x + 4
b) 1/2(16x + 8) = 8x + 4
c) 2(4x + 2) = 8x + 4
d) 2x(4x + 2) = 8x² + 4x
Answer:
82.62
Step-by-step explanation:
Mean score (μ) = 80
Standard deviation (σ) = 5
The 70th percentile of a normal distribution has an equivalent z-score of roughly 0.525.
For any given score, X, the z-score can be determined by:

For z = 0.525:

A raw score of approximately 82.62 corresponds to the 70th percentile.