Question

Find the equation of a line

Answer 1

Answers:

y=2x2−20x+51

Step-by-step explanation:

Vertex:

(5,1)

Focus:

(5,98)

Axis of Symmetry:

x=5

Directrix:

y=78

Answer 2

1) A(1;2) and slope=3.

slope-interception form is y=s*x+i, where s - slope, i - interception.

if to substitute the given coordinates and slope into the equation, then 2=3*1+i, ⇒ i=-1. It means, the required equation is:

y=3x-1.

2) A(1;2) and B(3;-2).

the common form is:

$\frac{x-X_B}{X_A-X_B} =\frac{y-Y_B}{Y_A-Y_B}.$

If to substitute the given coordinates into the common form, then:

$\frac{x-3}{1-3} =\frac{y+2}{2+2} ; \ => \ \frac{x-3}{-2} =\frac{y+2}{4}; \ => \ y=-2x+4.$