Question

I really need help! I'm stuck.

Answer 1

y-axis = altitude in feet

x-axis = minutes

slope = y/x = feet/minute

According to above data, we know that 1800 feet is y-intercept and slope is -300 feet per minute (why slope is negative? because its approaching ground at a constant speed)

a. slope = -300

  y-intercept = 1800

b. y = -300 x + 1800

c. Here we are given x = 2 minutes

y = -300(2) + 1800

y = -600 + 1800

y = 1200

The balloon will be 1200 feet high above the ground in 2 minutes.

d. Here we are given 300 feet which is y, and find x minutes.

y = -300 x + 1800

300 = -300x + 1800

300 - 1800 = - 300x

-1500 = -300x

1500 = 300 x

x = 1500 / 300

x = 5

The balloon will reach 300 feet above the ground in 5 minutes.

e. It asking when the balloon will reach the ground, if the balloon reaches the ground than the height will be 0, therefore x-intercept (y=0).

y = -300 x + 1800

0 = -300 x + 1800

-1800 = -300x

1800 / 300 = x

x = 6

The balloon will reach the ground in 6 minutes.

//Hope this helps