Question

URGENT PLEASE HELP!!!!!

1. Which best describes the equation y/6=x?
A. The relationship shows an inverse variation with a constant of variation of -6
B. The relationship shows an inverse variation with a constant of variation of -1/6
C. The relationship shows an inverse variation with a constant of variation of 1/6
D. The relationship does not show an inverse variation.

2. If y varies inversely with x and y=5 when x=2.5, what is the value of y when x=20?
A. 0.1
B. 0.625
C. 0.3125
D. 1.6

3. The current, I, in a circuit varies inversely with the resistance, R. If the resistance is 12 when the current is 3, what is the resistance when the current is 6?
A. 1/6
B. 1.5
C. 6
D. 24

Answer 1

(1)

we are given

`(y)/(6) =x`

we can find for y

multiply both sides by 6

`(y)/(6)*6 =6*x`

`y=6x`

we can see that y is directly proportional to x

so, option-D........Answer

(2)

y varies inversely with x

so, we can write it as

`y=k(1)/(x)`

now, we are given

y=5 when x=2.5

so, we can plug it here

`5=k(1)/(2.5)`

and then we can solve for k

`5*2.5=2.5*k(1)/(2.5)`

`k=12.5`

now, we can plug back

`y=(12.5)/(x)`

we can plug x=20

`y=(12.5)/(20)`

`y=0.625`.............Answer

(3)

we are given

The current, I, in a circuit varies inversely with the resistance, R

so, we can write it as

`I=(k)/(R)`

we have R=12 when I=3

so, we can plug it

`3=(k)/(12)`

now, we can solve for k

`3*12=12*(k)/(12)`

`k=36`

now, we can plug back

`I=(36)/(R)`

we can plug R=6

`I=(36)/(6)`

`I=6`................Answer