Answer:
third option
Step-by-step explanation:
Given
x² + 4x - 4 = 0 ( add 4 to both sides )
x² + 4x = 4
Using the method of completing the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(2)x + 4 = 4 + 4, that is
(x + 2)² = 8 ( take the square root of both sides )
x + 2 = ± = ± 2
( subtract 2 from both sides )
x = - 2 ± 2
Answer:
55.38 min
Step-by-step explanation:
A car travels,
182 km ⇒ 4 hours
And we have to find the time that it takes to travel 42 km .
Lets make a equation.
Let the unknown time be x
182 km ⇒ 4 hours
42 km ⇒ x
To make easy let's km in to meters and hours in to minutes
182000 m ⇒ 240 min
42000m ⇒ x
Now use cross multiplication.
Hope this helps you.
Let me know if you have any other questions :-)