If this is a slope question then:
We know that the formula for slope is:
y = mx + b ( M being slope, X being the x- intercept and y being the y-intercept)
So if the question asks to write an equation of the line with a x-intercept of -5 and a y- intercept of 15.
So now you substitute -5 for the x-intercept, and 15 for the y-intercept:
So now it's
y = 15m + -5
The m stays since there's no value for m.
So the final answer is: y = 15m + -5
