X representa o numero das suas respostas certas.
y represnta o numero das suas respostas erradas.
O total de perguntas <span>é 25, portanto
x + y = 25
Agora tratamos do dinheiro.
Come</span>ça com <span>R$ 500,00
Pelas x respostas certas, recebe 200x.
Pelas y respostas errads perde 150y.
O total de dineheiro inicial mais os ganhos menos as perdas s</span>ão iguais a
R$ 600,00, portanto
500 + 200x - 150y = 600
200x - 150y = 100
20x - 15y = 10
Temos um sistema de duas equações com duas variaveis.
<span>x + y = 25</span>
20x - 15y = 10
15x + 15y = 375
+ 20x - 15y = 10
---------------------------
35x = 385
x = 11
x + y = 25
11 + y = 25
y = 14
Resposta: Errou 14 perguntas.
My answer is prob 20 miles......
Answer:
area of the sector = 360π cm²
Step-by-step explanation:
To calculate the area of the sector, we will follow the steps below;
First write down the formula for calculating the area of a sector.
If angle Ф is measured in degree, then
area of sector = Ф/360 × πr²
but if angle Ф is measured in radians, then
area of sector = 1/2 × r² × Ф
In this case the angle is measured in radiance, hence we will use the second formula
From the question given, radius = 15 cm and angle Ф = 8π/5
area of sector = 1/2 × r² × Ф
=1/2 × 15² × 8π/5
=1/2 ×225 × 8π/5
=360π cm²
area of the sector = 360π cm²