15. Marley gets on an elevator on the 30th floor of a building. She goes up 6 floors to pick up a package then goes down 14 floors for a meeting. Write and simplify an expression to show what floor Marley is now on pls help ​

Step-by-step explanation:

The initial level is 30.

let the upward travel be +X and downward travel be -Y.

so the expression for her current level be ,

30+X-Y = 30+6-14= 22.

22 is her current level.

step-by-step explanation:

the ratio of red paint to blue paint is always 9/7. that means that, whatever x's value, (4x+12)/(4x-4) has that same ratio. so, set up an equation and cross-multiply to solve for x:

9/7 = (4x+12)/(4x-4)

9(4x-4) = 7(4x+12)

36x - 36 = 28x + 84

8x - 36 = 84

8x = 120

x = 15