Question

A line passes through the points (–3, –4) and (6, 2). What number is the x-intercept?

A –3
B –2
C 2
D 3

Answer 1

Answer: the answer is D

Explanation:

Answer 2

D. 3

Explanation:

`\bold{METHOD\ 1}`

`\text{The formula of a slope:}\\\\m=(y_2-y_1)/(x_2-x_1)\\\\\text{x-intercept:}\ (x,\ 0).\\\\\text{Susbtitute the coordinates of the points to the formula of a slope}\\\\(-3,\ -4),\ (6,\ 2),\ (x,\ 0):\\\\m=(2-(-4))/(6-(-3))=(2+4)/(6+3)=(6)/(9)=(6:3)/(9:3)=(2)/(3)\\\\m=(0-2)/(x-6)=(-2)/(x-6)\\\\\text{Therefore we have the equation:}\\\\(-2)/(x-6)=(2)/(3)\qquad\text{cross multiply}\\\\2(x-6)=(-2)(3)\\\\2(x-6)=-6\qquad\text{divide both sides by 2}\\\\x-6=-3\qquad\text{add 6 to both sides}\\\\x=3`

`\bold{METHOD\ 2}\\\\\text{Look at the picture.}`

Mark points in the coordinate system.

Lead a line through these points.

Read x-intercept.