Evaluate the expression when w=4,x=-11.7, and z = -5.4

I'm not sure but it might be 21.1 (I think)

 I can't read the attached photo well, so I will assume the following:

Equation: w + x -z

Values:  w=4, x=-11.7, z = -5.4

If so, the answer is -2.3

Step-by-step explanation:

4 -11.7 -(-5.4) = -2.3

this is a direct variation proportion. y = kx

y is the total amount due, k is the constant of variation, and x is the number of texts sent.

plug in the 3.20 and the 16 to solve for the "k". this is the constant of proportionality. it is the value that will not change.

3.20 = k(16). solving you get $.20 per text.

the equation would then be y = .20x