
Doug C. answered 09/25/22
Math Tutor with Reputation to make difficult concepts understandable
The fact that h(5) = -1 is similar to stating that in an x-y coordinate plane the function passes through (5, -1).
Similarly the function passes through (-2, 13).
So, how to you find the equation of a line (the function is given to be linear) when you know two points?
- Find the slope of the line using m = (y2-y1)/(x2-x1).
- Use point-slope (or slope-intercept) form to write the equation.
- Use function notation to write the equation for h(x).
m = 14/-7 = -2
Using point-slope:
y - 13 = -2 (x+2) (could have used either point as (x1,y1))
y = -2x-4+13
y = -2x+9
h(x) = -2x+9
h(5) = -10+9=-1
h(-2) = 4+9=13
Take a look at this Desmos graph to see how you can do these calculations there:
desmos.com/calculator/rsrbe8yf8n