Exam question help

“A point P lies on the line y= 4-3x. The point p is a distance squared root 34 from the origin. Find two possible positions of P.” I dont get this at all, it doesnt come with a diagram just a worded question

Original post by Luciehkd

“A point P lies on the line y= 4-3x. The point p is a distance squared root 34 from the origin. Find two possible positions of P.” I dont get this at all, it doesnt come with a diagram just a worded question

If it lies on that line at

x=p

, then it has coordinates

(p,4-3p)

. So, what is the distance of it from the origin in terms of

p

? This is just applying Pythagoras' Theorem.

(edited 6 years ago)

Reply 2

RogerOxon

21

Original post by Luciehkd

“A point P lies on the line y= 4-3x. The point p is a distance squared root 34 from the origin. Find two possible positions of P.” I dont get this at all, it doesnt come with a diagram just a worded question

Sketch the line, marking where it crosses the axes. Now draw a circle of radius ~6 (so that you get the intersections in approximately the right locations), centered on the origin. This should show you (approximately) the two points that you're after.

The maths is actually a little simpler. Any point on the line can be written as (x, 4-3x). Can you write a formula for the distance from the origin to that generic point? Solve for that being root 34.

Please post your workign if you have any issues.

Reply 3

Luciehkd

OP

5

It cant be, its not a right angled triangle.. im so confused

Reply 4

Rockers.

2

Original post by Luciehkd

“A point P lies on the line y= 4-3x. The point p is a distance squared root 34 from the origin. Find two possible positions of P.” I dont get this at all, it doesnt come with a diagram just a worded question