Answer:
The main reason it was important to study this group was:
1) If Whitehead had found that many people had drunk water from the Broad Street pump and not caught cholera, that would have been evidence against Snow's hypothesis.
Step-by-step explanation:
But Dr. John Snow was able to convince many councillors who ensured that the pump handle was removed from the Broad Street pump. Within a few days of this removal, the cholera epidemic ended. This step proved that Dr. Snow was right from the beginning. The pump handle was the means that the cholera epidemic was being spread from one person to another within Broad Street area, since many usually fetch water from the pump.
Answer:
x= -5
Step-by-step explanation:
(3x-4) (x+5).=0
=3x-4x+5=0.
x=-5
i think its -9118 sorry if im wrong
The geometry technique that Chee uses to find the height of the goalpost is the equal ratio of the corresponding sides of similar triangles.
Correct response:
- The eight of the goalpost is approximately <u>16.91 meters</u>.
<h3>Methods used to calculate the height</h3>
The length Chee is using the mirror to measure = The height of her school's football goalpost
The distance of the mirror from the goalpost = 14.35 meters
The distance on the other side of the mirror Chee steps to = 1.4 meters
The distance from her eyes to the ground = 1.65 meters
Required:
How tall is the goalpost.
Solution:
By using similar triangles relationships, we have;
Which gives;
- The height of the goalpost, h ≈ <u>16.91 meters</u>
Learn more about similar triangles here:
brainly.com/question/10676220
Vamos lá.
<span>Pede-se para determinar o parâmetro "m" da equação abaixo, sabendo-se que uma raiz é nula e a outra é positiva: </span>
<span>x² + mx + m² - m - 12 = 0 </span>
<span>Veja que se uma raiz é nula (é igual a zero), então vamos substituir o "x" por "0", na equação acima: </span>
<span>0² + m*0 + m² - m - 12 = 0 </span>
<span>0 + 0 + m² - m - 12 = 0 </span>
<span>m² - m - 12 = 0 ------resolvendo essa equação do 2º grau você encontrará as seguintes raízes: </span>
<span>m' = -3 </span>
<span>m'' = 4 </span>
<span>Dessa forma, vamos substituir "m" por (-3) e por 4 e ver se a equação terá uma raiz nula e outra positiva. Vamos ver? </span>
<span>Substituindo "m" por "-3", ficamos com: </span>
<span>x² - 3x + (-3)² - (-3) - 12 = 0 </span>
<span>x² - 3x + 9 + 3 - 12 = 0 </span>
<span>x² - 3x +12 - 12 = 0 </span>
<span>x² - 3x = 0 <------Veja que as raízes dessa equação são: x' = 0 e x'' = 3 </span>
<span>Veja que para m = -3, a equação se verifica, pois temos uma raiz igual a "0" e a outra positiva (igual a 3). </span>
<span>Agora vamos substituir "m" por 4 na equação original: </span>
<span>x² + 4x + 4² - 4 - 12 = 0 </span>
<span>x² + 4x + 16 - 16 = 0 </span>
<span>x² + 4x = 0 <----- Veja que as raízes dessa equação são: x' = 0 e x'' = -4. </span>
<span>Observe que, para m = 4, a equação NÃO se verifica, pois temos uma raiz igual a "0" e a outra negativa (igual a -4). E no enunciado é informado que uma raiz deverá ser nula e a outra positiva. Como deu uma nula e a outra negativa, então m = 4 não convém. </span>
<span>Logo, o valor de "m" deverá ser: </span>
<span>m = -3 <----Pronto. Essa é a resposta. </span>
