The Student Room Group
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>

Maths HELP Needed Sample Question

Capture.PNG

Anyone know how to solve this STEP BY STEP!
[QUOTE=NothingButWaleed;67109102]Capture.PNG

Anyone know how to solve this STEP BY STEP!

1) Work out the gradient AB
2) find M
3) substitute the point of c into y1-y=m(x-x1)

Y1 = the y coordinate of C
X1 = the X coordinate of X

X and Y stay the same so you just substitute numbers in.
Reply 2
Avatar for Aamna-
Aamna-
13
Okay, so the coordinates of A and B are (-3, 0) and (0,5) respectively.
To find the gradient of line AB, you just find the difference in y and divide by the difference in x. 0-5/-3-0 = -5/-3 = 5/3, so the line AB has an equation like this: y =5/3x + c.

We're told to find the perpendicular of AB, which is just the negative reciprocal of the gradient. So, you basically flip and add a negative sign 5/3 -> -3/5. So the equation of the line we want is y = -3/5x + c.

It also passes through C which is (4, -2), so we put that into the equation y = -3/5x+c.
-2 = -3/5(4) + c
-2 = -12/5 + c
-2 + 12/5 = c
c = 2/5

Therefore, the equation of the line which is perpendicular to AB and passes through C is: y = -3/5x + 2/5. Hope I've explained it clearly enough.


Posted from TSR Mobile
Original post by Aamna-
Okay, so the coordinates of A and B are (-3, 0) and (0,5) respectively.
To find the gradient of line AB, you just find the difference in y and divide by the difference in x. 0-5/-3-0 = -5/-3 = 5/3, so the line AB has an equation like this: y =5/3x + c.

We're told to find the perpendicular of AB, which is just the negative reciprocal of the gradient. So, you basically flip and add a negative sign 5/3 -> -3/5. So the equation of the line we want is y = -3/5x + c.

It also passes through C which is (4, -2), so we put that into the equation y = -3/5x+c.
-2 = -3/5(4) + c
-2 = -12/5 + c
-2 + 12/5 = c
c = 2/5

Therefore, the equation of the line which is perpendicular to AB and passes through C is: y = -3/5x + 2/5. Hope I've explained it clearly enough.


Posted from TSR Mobile


Let's restrain from posting full solutions, shall we? We can only point him/her in the right direction otherwise we'd be doing his/her maths for him/her without him/her putting thought into it. The post above is sufficient help.
(edited 7 years ago)

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you