Remember the equation of a line with slope m and y-intercept b:
![y=mx+b](https://img.qammunity.org/2023/formulas/mathematics/high-school/smsb8cbft03lwblmi49nf2l6jby2ofxzws.png)
Which can be expressed in terms of functions by replacing y=f(x)
![f(x)=mx+b](https://img.qammunity.org/2023/formulas/mathematics/high-school/6o509bhbp213rd8y4ne1d5fl5x7nzt1y7d.png)
Any line with the same slope will be parallel to that equation.
By comparing with:
![f(x)=-5x+6](https://img.qammunity.org/2023/formulas/mathematics/college/605n0xiabe1fsc4xhxcrpp7uhgdgsnuytb.png)
We can know that its slope is equal to -5.
Since the "parallel slope" is just the slope, then