How do you simplify #5x^2 – 1 = 74#?

Question

1292 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-07-31T20:20:24

#x=±sqrt 15#

#5x^2-1=74#

#5x^2=74+1#

#cancel(5)x^2=cancel(75)#

#x^2=15#

#sqrt(x^2)=sqrt15#

#x=±sqrt 15#

Answer 2 · 2016-07-31T20:21:18

#x=+-sqrt(15)#

add 1 to both sides

#5x^2=75#

Divide both sides by 5

#x^2=15#

Square root both sides

#x=+-sqrt(15)#