It goes 2, 4, 10, 20 euros
(1,2)
(2,4)
(5,10)
(10,20)
y² - 4y - 2x - 4 = 0
<u> +2x +4 </u> <u>+2x + 4 </u>
y² - 4y = 2x + 4
<u> +4 </u> <u> +4 </u>
(y - 2)² = 2x + 8
<u> -8 </u> <u> -8 </u>
(y - 2)² - 8 = 2x
(y - 2)² - 4 = x
x = (y - 2)² - 4
<em>Note: this is a parabola whose axis of symmetry is y = 2 and vertex is (-4, 2)</em>
When two parallel lines are intersected by a transversal line, forming the angles that are supplementary