Answer:
(5.871 `; 6.127)
Step-by-step explanation:
Given :
Mean = 6
Standard deviation. σ = 0.5
Samplr size, n = 100
Zcritical at 99% confidence = 2.58
The confidence interval :
Mean ± margin of error
Margin of Error = Zcritical * σ / sqrt(n)
Margin of Error = 2.58 * 0.5/sqrt(100) = 0.129
Confidence interval :
Lower boundary = 6.00 - 0.129 = 5.871
Upper boundary = 6.00 + 0.129 = 6.129
(5.871 `; 6.127)
4x² + 2x - 30 = 0
<span>
factor out the GCF:
</span>2(2x² + x - 15) = 0
<span>
factor the trinomial completely:
2x</span>² + x - 15 = 0
2x² + 6x - 5x - 15 = 0
2x(x + 3) - 5(x + 3) = 0
(2x - 5)(x + 3) = 0
<span>use the zero product property and set each factor equal to zero and solve:
2x - 5 = 0 or x + 3 = 0
2x = 5 x = -3
x = 2.5
</span><span>The roots of the function are x=-3, x=2.5</span>
Answer: Associative property of addition
I hope this helps :D
