The rise or an increase in altitude is represented by positive sign and a decend or decrease in altitude is represented by negative sign.
First the helicopter descended 1200 feet. So the change in altitude will be -1200 feet.
Then the helicopter rose by 800 feet. So the change in altitude will be 800 feet.
Finally the helicopter descended by 450 feet. So the change in altitude will be -450 feet.
The net change in altitude will be the sum of all the above 3 changes.
Change in altitude = -1200 + 800 - 450 = -850 feet
The negative sign indicates a descend i.e. loss in altitude. So the net change in altitude was a loss of 850 feet.
Answer:
just practice time and again practice might not make perfect but it surely makes better. relying when your teacher only might not help you must mostly rely on your hard work and also have people at your disposal to help you including the said teacher hope you'll improve
My "work" is to enter the equations into a graphing calculator and let it show me the answers--just as your "work" is to copy the question to Brainly.
The solutions are
(x, y) = (-0.5, 7.5)
(x, y) = (3, 25)
_____
When you equate the expressions for y, you get the quadratic
2x² -5x -3 = 0
(2x +1)(x -3) = 0
x = -1/2 or 3
y = 5(x +2) = 15/2 or 25
