Which of the following are solutions to the equation below? check all that apply. 4x2 - 81 = 0 a. 9 b.-9/2 c.-2/9 d.-9 e.9/2 f.2/9

B. -9/2 and E. 9/2

Step-by-step explanation:

4x² - 81 = 0

Add 81 to bothside

4x² - 81 + 81 = 0+ 81

4x² = 81

Divide bothside by 4

4x²/4 = 81 /4

x² = 81/4

Take the square root of both side

√ x² = ±√81/4

x = ± 9/2

x = -9/2 or x = 9/2

x = -9/2 or 9/2

65°

step-by-step explanation:

the total measure of a triangle is 180 degrees. 62 + 53 is 115.

180 - 115 = 65

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m