Answer:
y = 2x + 4
Step-by-step explanation:
the equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
calculate m using the slope formula
m = 
with (x₁, y₁ ) = (- 2, 0) and (x₂, y₂ ) = ( 0, 4) ← 2 points on the line
m =
=
=
= 2
the line crosses the y- axis at (0, 4 ) ⇒ c = 4
y = 2x + 4 ← equation of line
keeping in mind that standard form for a linear equation means
• all coefficients must be integers, no fractions
• only the constant on the right-hand-side
• all variables on the left-hand-side, sorted
• "x" must not have a negative coefficient
![\bf (\stackrel{x_1}{-1}~,~\stackrel{y_1}{-5})~\hspace{10em} \stackrel{slope}{m}\implies \cfrac{2}{3} \\\\\\ \begin{array}{|c|ll} \cline{1-1} \textit{point-slope form}\\ \cline{1-1} \\ y-y_1=m(x-x_1) \\\\ \cline{1-1} \end{array}\implies y-\stackrel{y_1}{(-5)}=\stackrel{m}{\cfrac{2}{3}}[x-\stackrel{x_1}{(-1)}]\implies y+5=\cfrac{2}{3}(x+1)](https://tex.z-dn.net/?f=%5Cbf%20%28%5Cstackrel%7Bx_1%7D%7B-1%7D~%2C~%5Cstackrel%7By_1%7D%7B-5%7D%29~%5Chspace%7B10em%7D%20%5Cstackrel%7Bslope%7D%7Bm%7D%5Cimplies%20%5Ccfrac%7B2%7D%7B3%7D%20%5C%5C%5C%5C%5C%5C%20%5Cbegin%7Barray%7D%7B%7Cc%7Cll%7D%20%5Ccline%7B1-1%7D%20%5Ctextit%7Bpoint-slope%20form%7D%5C%5C%20%5Ccline%7B1-1%7D%20%5C%5C%20y-y_1%3Dm%28x-x_1%29%20%5C%5C%5C%5C%20%5Ccline%7B1-1%7D%20%5Cend%7Barray%7D%5Cimplies%20y-%5Cstackrel%7By_1%7D%7B%28-5%29%7D%3D%5Cstackrel%7Bm%7D%7B%5Ccfrac%7B2%7D%7B3%7D%7D%5Bx-%5Cstackrel%7Bx_1%7D%7B%28-1%29%7D%5D%5Cimplies%20y%2B5%3D%5Ccfrac%7B2%7D%7B3%7D%28x%2B1%29)

Answer:
the formula is C = 2(pi)r