Use the given conditions to write an equation for the line in slope-intercept form

Question

Passing through (-5,3) and perpendicular to x+4y=-4

Answer 1

Hi Garrett;

x+4y=-4

This equation is in standard form...

Ax+By=C

slope is -A/B

-1/4

The slope of the line perpendicular to this is the negative reciprocal of -1/4...

4

Point-slope formula...

y-y₁=m(x-x₁)

m is slope...

point provided is (-5,3)

y-3=4(x--5)

Subtracting a negative number is the same as adding a positive number...

y-3=4(x+5)

y-3=4x+20

Add 3 to both sides...

y-3+3=4x+20+3

y=4x+23

Formula is now in slope-intercept form...

y=mx+b

m is the slope.

b is the y-intercept, value of y when x=0.

 

Let's check our results...

(-5,3)

y=4x+23

3=[(4)(-5)]+23

3=-20+23

3=3