136k views
20 votes
Which is the correct equation for a line that has a slope of 2 and passes through the point (-1, -5). Use the graph below or graph paper if needed.

PLEASE HELP ASAP
A.y = 2x - 5

B.y = 2x + 5

C.y = 2x - 3

D.y = 2x + 3

Which is the correct equation for a line that has a slope of 2 and passes through-example-1
User Rgommezz
by
4.5k points

1 Answer

10 votes

9514 1404 393

Answer:

C. y = 2x - 3

Explanation:

The y-intercept (b) can be found from ...

y = mx + b

y - mx = b . . . . . subtract mx

Here, you are given (x, y) = (-1, -5) and slope m = 2.

b = -5 -2(-1) = -5+2 = -3

The correct equation is ...

y = 2x -3 . . . . . matches choice C

_____

On the graph, you can plot point (-1, -5) left of the y-axis 1 unit and down from the x-axis 5 units. The slope of 2 tells you the line will rise 2 units from there to a y-value of -3 when it runs 1 unit to the right to an x-value of 0. That point (0, -3) is the y-intercept, showing you that choice C is correct.

User Squeaky
by
4.6k points