Line qr goes through points q(0, 1) and r(2, 7). which equation represents line qr?

y – 1 = 6x
y – 1 = 3x
y – 7 = 2x – 6
y – 7 = x – 2

We write the equation in the form of directional.

y -1 = 6x               ⇔    y = 6x + 1
y - 1 = 3x              ⇔    y = 3x + 1
y - 7 = 2x - 6         ⇔    y = 2x - 6 + 7 
                                     y = 2x + 1
y - 7 = x - 2           ⇔    y = x - 2 + 7
                                     y = x + 5

Equations cleverly arranged .
Point Q = (0,1)  
b factor , not only fits the last equation
In the drawing have engraved points Q and R are tangent linear function appropriate to that point . This graphics solution . y = 3x + 1
Answer b

We check choice by the system of equations , where substitute wartoćsi points Q and R to the model equations linear function



The result of equations confirmed our choice Answer b

Figure I'll add soon