Here are the questions:
I have posted a link there to this topic so the OP can see my work.Word problems involving quadratics?
1.) The owner of an apartment building with 50 units has found that if the rent for each unit is $3,600 per month, all of the units will be filled. But one unit will become vacant for each $100 increase in the rent. What monthly rent would maximize the monthly income? What is the maximum income?
2.) If a gun is fired upward with a velocity of 100 m/s, its height after t seconds is -5t^2+100t meters. At what time will the bullet be 250 m. high?
3.) In driving to Manila, a motorist discovered that he could make the trip in the expressway in 2 hrs. less time by increasing his speed by 9 km/h. What was his original speed?
Can you please solve these? And if you have time, kindly explain this for me. thanks