Someone help, please | If y varies directly with x, and y = -20 and x = 5, what is x when y = -30?

x = 7.5

Step-by-step explanation:

y is directly proportional to x

Formula:

y=k x (k represent as the proportion)

Substitute to given detail

When y=-20, x=5.

•At this point you need to solve k for the proportion.

-20=k(5)

5k=-20

k=-4 (Must be shown, youll be awarded mark(s) )

•Use k=-4 to complete the second equation.

When y= -30,

-30= (-4)x

-4x= 30

x= -(30/4)

x=-7.5

-7.5 Is the final answer

Step-by-step explanation:

18+ 5(2x + 5) = 12

18 + 10x + 25 = 12

43 + 10x = 12

10x = 12 -43

10x = -31

x = -3.1