Question

Write an equation for (2, 1), and y increases by 4 when x increases by 1.

Answer 1

Answer:

Step-by-step explanation:

The equation for a line can be written in slope-intercept form:

$y = mx + b$

Where $m$ is the slope of the line and $b$ is the y-intercept.

Since we know "$y$ increases by $4$ when $x$ increases by $1$", that tells us that the slope of the line is $4$.

$y = 4x + b$

To figure out the y-intercept, $b$, we can plug in the coordinates given in the problem to the point that the line passes through, $(2, -1)$

$1 = 4(2) + b$

$1 = 8 + b$

$b = -7$

Therefore, the equation of the line is $y = 4x - 7$