Question

What is an equation of the line that passes through the point (4,-1) and has a slope of -2?

Answer 1

Answer:

Option C, $y = -2x + 7$  

Step-by-step explanation:

1) Slope-intercept format is represented by the formula $y = mx + b$. By looking at the options, we can see that all of them follow this format.  

So, first, we can identify which equations have a slope of -2 to narrow down our options. In slope-intercept form, the coefficient of the x-term, or $m$, represents the slope. So, this narrows the answer down to options b and c because they are the only ones that have $m$ as -2.  

2) Next, in order to find which equation is the right answer, we can substitute the x and y values of the given point (4, -1) into both equations, then simplify. Whichever equation results in a true statement must be the answer. Let's try option c first. Substitute 4 for x and -1 for y:

$-1=4(-2)+7\\-1 = -8+7\\-1=-1$

-1 does equal -1, so this statement is true. Thus, option c must be the answer.