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What is the equation of the line that passes through the point (-4, -3) and has a slope of 5?

y = 5x - 17
y = 5x - 11
y = 5x + 11
y = 5x + 17

1 Answer

4 votes

Answer:

y = 5x + 17

Last choice

Explanation:

The equation for a line can be written in the form y = mx + b. (This is called slope-intercept form).

"x" and "y" mean points on the line.

"m" means the slope of the line, which is how steep the line is.

"b" means the y-intercept, which is when the line hits the y-axis.

To write an equation in slope-intercept form, we need the slope and y-intercept.

We know the slope needs to be 5.

m = 5

We know one point on the line, (-4, -3). Points are written (x, y), so:

x = -4

y = -3

Substitute the numbers we know for "m", "x" and "y" into the equation for a line. Then, we can isolate 'b' to know what it equals.

y = mx + b

-3 = (5)(-4) + b Multiply to simplify

-3 = -20 + b Start isolating 'b'

-3 + 20 = -20 + 20 + b Add 20 to both sides to cancel out on the right.

-3 + 20 = b Solve the left side.

17 = b Answer

b = 17 Put variable on left side for standard formatting

Now that we know m = 5 and b = 17, rewrite the equation in the form y = mx + b.

y = 5x + 17

User Nathaniel Gentile
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