Answer:
C
Step-by-step explanation:
Given
2x² + x - 1 = 2 ( subtract 2 from both sides )
2x² + x - 3 = 0
Consider the factors of the product of the coefficient of the x² term and the constant term which sum to give the coefficient of the x- term.
product = 2 × - 3 = - 6 and sum = + 1
The factors are - 2 and + 3
Use these factors to split the x- term
2x² - 2x + 3x - 3 = 0 ( factor the first/second and third/fourth terms )
2x(x - 1) + 3(x - 1) = 0 ← factor out (x - 1) from each term
(x - 1)(2x + 3) = 0
Equate each factor to zero and solve for x
x - 1 = 0 ⇒ x = 1
2x + 3 = 0 ⇒ 2x = - 3 ⇒ x = - 
Answer:
96 in^2
Step-by-step explanation:
area of rectangle: 24*8=192
Area of triangle: (1/2)*base*height
= .5 * 8 * 24
=192/2
=96
area of shaded=rectangle - triangle
= 192-96
which is also just 192/2
so it is 96
Answer:
9/32
Step-by-step explanation:
3 5/9
=> (27+5)/9
=> 32/9
Reciprocal of 32/9 is,
=> 9/32
Answer:
B. z Subscript alpha divided by 2 zα/2 = 1.96.
Step-by-step explanation:
We are given that we want to construct a confidence interval. For this, the summary statistics for randomly selected weights of newborn girls:
n = 236,
= 30.3 hg, s = 7.2 hg. The confidence level is 95%.
As we can clearly see here that the population standard deviation is unknown and the sample size is also very large.
It has been stated that when the population standard deviation is unknown, we should use t-distribution but since the sample size is very large so we can use z distribution also as it is stated that at very large samples; the t-distribution corresponds to the z-distribution.
Here,
= level of significance = 1 - 0.95 = 0.05 or 5%
= 0.025 or 2.5%
So, the value of
in the z table is given as 1.96 with a 2.5% level of significance.