Respuesta:
2x - 0.5x = 30
x = 20
Explicación paso a paso:
Llamemos "x" a la incógnita, el número desconocido.
Cuando nos referimos al doble de un número, es lo mismo que 2x.
Cuando nos referimos a la mitad de un número, es lo mismo que 0.5 x.
Consideremos que al doble de un número (2x) se le resta su mitad 0.5x) y se obtiene 30. La ecuación resultante es:
2x - 0.5x = 30
1.5x = 30
x = 30/1.5 = 20
Answer:
the 3 one is the correct answer
Step-by-step explanation:
First, find what one lightbulb costs.
9.85 / 5 = 1.97
Then multiply the product by 7.
1.97 * 7 = 13.79
Seven light bulbs will cost $13.79
Given:
f(x) = 70n - 400 : equation for monthly profit.
n = number of students enrolled in the guitar class.
70 refers to the amount charged per student.
400 is the fixed expense made by the instructor.
For the instructor to have a profit, the product of 70n must be more than 400.
400/70 = 5.7 or 6
There must be at least 6 students enrolled in class for the instructor to generate profit.
f(x) = 70(6) - 400 = 420 - 400 = 20
1000 = 70n - 400
1000 + 400 = 70n
1400 = 70n
1400/70 = n
20 = n
There must be 20 students enrolled in class for the instructor to earn 1000 in profit.
1000 = 70(20) - 400
1000 = 1400 - 400
1000 = 1000
G(f(2)) means work out whatever f(2) is then plug this into g(x).
So f(2) is 3 because we just find the x-value 2 in the left hand column and read across. This is 3.
So then we find g(3) by finding the x-value 3 in the left hand column and read across. This is 10.
So g(f(2)) = 10
