Question

please help me.. What is the equation of the line that is perpendicular to -x + y = 7 and passes through (-1, -1)?

Answer 1

Perpendicular lines have opposite slopes.

-x + y = 7

First, convert to slope-intercept form:

-x + y = 7

Add 'x' to both sides:

y = x + 7

Now it's in the form of y = mx + b, where 'm' is the slope, so what's the slope here?

Answer 2

2 i think

Answer 3

No..it would be right before the 'x'..and that is '1'.

Answer 4

The opposite of 1 is -1.

So the slope will be -1.

Plug this in with the point to get the equation.

\(y - y_1 = m(x - x_1)\)

Where \(y_1\) is the y-value of the point, \(x_1\) is the x-value of the point, and \(m\) is the slope.

So we have:

\(y + 1 = -1(x + 1)\)

Distribute -1 into the parenthesis:

\(y + 1 = -x - 1\)

Add 1 to both sides, what's -1 + 1?

Answer 5

0 right?

Answer 6

Yes, so we have:

y = -x

Answer 7

That's our equation.