7. The sketch shows a painter standing on a scaffold that is supported by two ropes. The

person weighs 500 N and the force of each

rope is 400 N. Calculate the weight of the

scaffold.

Fr

Explanation:

From the question

Weight of painter = 500N

Weight of scaffold = x

Weight of painter + weight of scaffold = 2* 400 (since they are supported by two ropes)

Substitute

500 + x = 2(400)

500+x = 800

x =  800-500

x = 300N

Hence the weight of the  scaffold is 300N

answer: at 24 february, 2014 the population gets twice of its initial population.

explanation:

since we have given that

the population for alpha city, t years after january 1, 2004 is given as

first we find out the initial population, i.e. t=0,

so, our quadratic equation becomes,

according to question, we have said that if the population has twice its initial population, then it becomes

so, time taken to reach this above mentioned population is given by

now, we know that time can't be negative so, we take t=9.149 years.

hence, at 24 february, 2014 the population gets twice of its initial population.