Answer:
( x+1)^2 = 4
Step-by-step explanation:
x^2+2x-3=0
Add 3 to each side
x^2 +2x = 3
Take the coefficient of x
2
Divide by 2
2/2 =1
Square it
1^2 =1
Add to each side
x^2 +2x = 3
x^2 + 2x+1 = 3+1
( x+1)^2 = 4
Take the square root of each side
x+1 = ±2
Subtract 1 from each side
x+1-1 = -1 ±2
x = -1+2 x = -1-2
x =1 x = -3
Since the temperature dropped 2 degrees every hour, and there are 6 hours, make a equation 2(6) in which 6 replaces the x. Just multiply and the total temperature change will have been 12 degrees.
The first one would be 120 the second one would be 68