What number should be added to the expression x^2 + 4x to change it into a perfect square trinomial

choose all correct answers

4

1

8

2

4

Step-by-step explanation:

given

x² + 4x

To change it into a perfect square

add (half the coefficient of the x- term)² to x² + 4x

x² + 4x + ()²

= x² + 4x + 2² = x² + 4x + 4

and x² + 4x + 4 = (x + 2)² ← a perfect square

30 miles

step-by-step explanation:

we know that 60 seconds equals 1 minute and 60 minutes 1 hour

44 ft       60 sec     60 min     158400   ft

  *   *   =

1 sec       1 min       1 hour         hour

we know that there are 5280 ft per mile

158400   ft       1 mile         30 miles

  *   =

1   hour               5280 ft     1 hour

so in 1 hour   it can travel 30 miles