Amanda uses the equation y=kx to determine how much money she earns after working any number of hours (x). Amanda earned $350 after working 40 hours. What is the value of k in Amanda's equation?

Is this correct?

40* 8.75= $350

Yes. :-)

Which way do I write it?

y=kx

350 = 40k

350/40 = k

8.75 = k

350รท40=8.75

k = earnings per hour

Yes. But how did you find 8.75?