Answer:
c. observational study
Step-by-step explanation:
<em>Researchers compare the rates of autism for children who did and did not receive the standard measles-mumps-rubella vaccine, to see if the vaccine might be responsible for autism in some children.</em>
This study design in the above scenario is observational study because the researcher are obviously observing whether the vaccine is affecting the children. Note that Observational study is like experiment which attempts to understand the cause and effect relationships on a subject.
Answer:
10 percent
Step-by-step explanation:
i took a test
Answer:
26.8907563 or if your rounding it then 26.7
Step-by-step explanation:
Answer:
x = 15 or x = - 
Step-by-step explanation:
Cross- multiplying gives
(14x + 6)(17x + 5) = 9x(27x + 11) ( expanding factors )
238x² + 172x + 30 = 243x² + 99x
rearrange into standard form : ax² + bx + c = 0
5x² - 73x - 30 = 0 ← in standard form
consider the factors of the product 5 × - 30 = - 150 which sum to the coefficient of the x-term (- 73 )
the factors are - 75 and + 2
Use these factors to split the middle term
5x² - 75x + 2x - 30 = 0 ( factor by grouping )
5x(x - 15) + 2(x - 15) = 0 ← take out the factor (x - 15)
(x - 15)(5x + 2) = 0
equate each factor to zero and solve for x
x - 15 = 0 ⇒ x = 15
5x + 2 = 0 ⇒ x = - 
Answer: x=−10
Step-by-step explanation:
x−3−2(x+6)=−5
x+−3+(−2)(x)+(−2)(6)=−5(Distribute)
x+−3+−2x+−12=−5
(x+−2x)+(−3+−12)=−5(Combine Like Terms)
−x+−15=−5
−x−15=−5
−x−15+15=−5+15
−x=10