Answer:
x²+6x+9=0
x²+3x+3x+9=0
x(x+3)+3(x+3)=0
(x+3)(x+3)=0
either
x+3=0
x=-3
or
x+3=0
x=-3
Step-by-step explanation:
next method
x²+6x+9=0
x²+2×x×3+3²=0
it is in formula of (x+y)²
(x+3)²=0
x+3=√0
x+3=0
x=-3
0.706 is the answer to your problem
Given:
Sample Mean <span>= 30<span>
Sample size </span><span><span><span>= 1000</span></span><span>
</span></span></span>Population Standard deviation or <span><span><span>σ<span>=2</span></span><span>
</span></span>Confidence interval </span><span>= 95%</span>
to compute for the confidence interval
Population Mean or <span>μ<span><span>= sample mean ± (</span>z×<span>SE</span>)</span></span>
<span><span>where:</span></span>
<span><span>SE</span>→</span> Standard Error
<span><span>SE</span>=<span>σ<span>√n</span>= 30</span></span>√1000=0.9486
Critical Value of z for 95% confidence interval <span>=1.96</span>
<span>μ<span>=30±<span>(1.96×0.9486)</span></span><span>
</span></span><span>μ<span>=30±1.8594</span></span>
Upper Limit
<span>μ <span>= 30 + 1.8594 = 31.8594</span></span>
Lower Limit
<span>μ <span>= 30 − 1.8594 = <span>28.1406</span></span></span>
<span><span><span>
</span></span></span>
<span><span><span>answer: 28.1406<u<31.8594</span></span></span>
The regression equation:
y = m x + b
m = ( 57 - 50 ) / ( 178 - 168 ) = 7 / 10 = 0.7
50 = 0.7 * 168 + b
50 = 117.6 + b
b = 50 - 117.6
b = - 67.6
y = 0.7 * x - 67.6The graph is in the attachment.
The weight of supermodel who is 171 cm tall:
y = 0.7 * 171 - 67.6 = 119.7 - 67.6 =
52.1 kg
Answer its 82 i added the cm
