Algebra Answer Check Please?

Question

Please check these answers. If I'm wrong please show me the correct steps to finding the answers.

Write an equation in slope-intercept form for a line that passes through the given point and is perpendicular to the given line.

Q1. y = 4x - 7; (5, -1)

Q2. y = 3; (4, -2)

My Answers:
1. y = -1/4x - 21
2. x = 4

Thanks for the help!

Enjoy your dinner

Answer 1

2nd one is right

on the first one your slope is right. Once you have the slope you just need to put the point (5,-1) into the equation y=-1/4x+c and solve for c.

i get 1/4.

Answer 2

Chris, great job so far!

You did indeed get the correct slope for Q1. -1/4

you need to find the right y-intercept.

you must set up an equation for a line with the slope you determined, -1/4, that passes through the point (5,-1)

y=ax+b
y=(-1/4)x + b

now, substitute the values for x and y given by the point in question to solve for the y intercept, b.

-1=(-1/4)(5) + b
-1=-5/4 + b
b= 1/4

so the equation is y = (-1/4)x + 1/4, which you can check by substituting 5, -1 in for x and y and verifying it works. does it?

for Q2 you have the right equation. don't know if they will quibble about its being in slope intercept form or not. Of course, that's kinda hard with no y. :-)

but maybe 0=-x+4 just to be safe?

Good luck!

Hope this helps... you have a good understanding of slope! :-)

Answer 3

i'll answer this in a min,my mom's callin for dinner,gimme 5 mins,n no,im not a phoney