Ask Singapore Homework?
Upload a photo of a Singapore homework and someone will email you the solution for free.
Question
secondary 4 | A Maths
One Answer Below
Anyone can contribute an answer, even non-tutors.
Challenging question for functions.
y = ax² + bx + c
In this case, since we are measuring x from the centre, , the midpoint of the curve is on the y axis. So the value of b is 0.
Lowest height of the cable = 80m.
At the centre, x = 0, then y = c .
Since lowest height is 80m, c = 80.
If the two 200m-high towers are 1200m, then distance from the centre to either tower is half of it
= 600m
This also tells you that
y = 200 when x = 600 or -600
We can now come up with the following :
y = ax² + 80
Sub y = 200, x = 600(or -600, up to you)
200 = a(600²) + 80
200 = 360000a + 80
120 = 360000a
a = 120/360000
a = 1/3000
See 1 Answer