Answer
(a)
slope =$20$.
y-intercept: $(0, -50)$
x-intercept: $(2.5, 0)$
(b) $y=20x-50$
Work Step by Step
RECALL:
(1) The slope is the ratio rise (change in y) over run (change in x).
(2) The x-intercept is the point where the graph touches/crosses the x-axis.
(3) The y-intercept is the point where the graph touches/crosses the y-axis.
(4) The slope-intercept form of a line's equation is $y=mx+b$ where $m$=slope and $(0, b)$ is the line's y-intercept.
(a) From the point $(0, -50)$ to the point $(5, 50)$, the change in $y$ is $100$ while the change in $x$ is $5$. Thus, the slope is $\frac{100}{5}=20$.
The graph crosses the y-axis at the y-intercept $(0, -50)$.
With a slope of $20$, from $(0, -50)$, a increase of $2.5$ units in the value of $x$ gives a $50$ unit increase in $y$, leading to the x-intercept $(2.5, 0)$.
(b) With a slope of $20$ and a y-intercept of $(0, -50)$, then the equation of the line is $y=20x-50$.
