A level maths help

I need help with these two questions pelase, and anything will be appreciated thank you:

The rules of a sport say that the length, l m, and the width, w m of a playing field can be any value, provided the area is 120 m2. Use
logs to model the relationship
between l and w as a straight line
and show this on a sketch.

2)Scientists are monitoring the population of curly-toed spiders at a secret location. It appears to be dropping at a rate of 25% per year. When the population has dropped below 200, the species will be in danger of extinction.
At the moment the population is 2000. Use logarithms and solve an inequality to find the year in which the spiders will be in danger of extinction.

OP

Anyone?

area must be 120m^2
so lm=120
rewrite this in the from y=mx and show this on a plot

it's a gp with first term 2000 and common ratio 0.75
write the nth term in terms of n
use logs to find the value of n when the population gets below 200

Reply 3

Shannon.Leanne

OP

13

I’m still confused, can anyone help please?

Original post by Shannon.Leanne

I need help with these two questions pelase, and anything will be appreciated thank you:

The rules of a sport say that the length, l m, and the width, w m of a playing field can be any value, provided the area is 120 m2. Use
logs to model the relationship
between l and w as a straight line
and show this on a sketch.

2)Scientists are monitoring the population of curly-toed spiders at a secret location. It appears to be dropping at a rate of 25% per year. When the population has dropped below 200, the species will be in danger of extinction.
At the moment the population is 2000. Use logarithms and solve an inequality to find the year in which the spiders will be in danger of extinction.

Please post these in the Maths forum instead, otherwise they're likely to get overlooked and you get no decent responses!

For the first question, as said above, you have that