How do you solve #x^2=90#?

2 Answers
Jul 4, 2017

Answer:

x=+-3#sqrt#10

Explanation:

Taking the square root of any number gives you two answers, one positive and one negative e.g. -2 x -2 =4
Square root of 90 = square root of 9 x 10
You can root the 3 to give 3#sqrt#10

Jul 4, 2017

Answer:

#x=3sqrt(10) larr" exact value"#

Explanation:

Using the 'Principle square root'. That is, the positive one.

Square root both sides

#sqrt(x^2)=sqrt(90)#

#x=sqrt(3^2xx10)#

#x=3sqrt(10) larr" exact value"#

Not that the decimal equivalent would be rounded and thus not as precise.