Question

40 POINTS PLS HELP PLS PLS PLS PLS PLS PLS PLS PLS PLS PLS /J IM LAZY NO PLS HELP

Answer 1

Answer:

y = -0.5x - 3.5

Explanation:

Take two points: (1, -4), (3, -5)

Find slope:

$\sf slope: \dfrac{y_2 - y_1}{x_2- x_1} \ \ where \ (x_1 , \ y_1), ( x_2 , \ y_2) \ are \ points$

$\rightarrow \sf slope \ (m) : \dfrac{-5-(-4)}{3-1} = -\dfrac{1}{2}$

Equation:

$\sf y- y_1 = m (x - x_1)$

$\rightarrow \sf y- (-4) = -\dfrac{1}{2} (x -1)$

$\rightarrow \sf y+ 4 = -\dfrac{1}{2} x + \dfrac{1}{2}$

$\rightarrow \sf y = -\dfrac{1}{2} x + \dfrac{1}{2} - 4$

$\rightarrow \sf y = -0.5 x -3.5$

Answer 2

The formula of a line is:

$f(x) = kx + b$

k — stands for tg of line angle
b — stands for the y value of a point where the line crosses y axis.

We can see 2 points:
A (1, -4)
B (3, -5)

We can make a system of equations:

$k*1+b=-4\\k*3+b=-5$

From second equation:

$b = -5 - 3k$

Let's put b in first equation:

$k-5-3k=-4\\-2k=1\\k=- \frac{1}{2}$

Now we can find b:

$b = -5 -3*- \frac{1}{2}\\b = -5 + 1.5\\b = -3.5$

The answer is:
-0.5x -3.5