Question

Sabendo que a reta r passa pelo ponto A(1/2,-2/3) e tem coeficiente angular igual a 5, a equação da reta r é:

A) y=5x-19/6
B) y= -26/15x+5
C) y=5x-1/2
D) y=-2/3x+5

Answer 1

Sendo
$A( \frac{1}{2} ,- \frac{2}{3} ) \\ \\ m=5 \\ \\ y-y_A=m(x-x_A) \\ \\ y-(- \frac{2}{3} )=5(x- \frac{1}{2} ) \\ \\ y+ \frac{2}{3} =5x- \frac{5}{2} \\ \\ mmc=6 \\ \\ 6y+4=30x-15 \\ \\ 6y=30x-15-4 \\ \\ 6y=30x-19 \\ \\ y= \frac{30x}{6} - \frac{19}{6} \\ \\ y=5x- \frac{19}{6} \mapsto letra~~ A$