Question
Solve the inequality
Solve the inequality by testing the values in the interval
Solve for x
−25<x<25
Alternative Form
x∈(−25,25)
Evaluate
x2<20
Move the expression to the left side
x2−20<0
Rewrite the expression
x2−20=0
Move the constant to the right-hand side and change its sign
x2=0+20
Removing 0 doesn't change the value,so remove it from the expression
x2=20
Take the root of both sides of the equation and remember to use both positive and negative roots
x=±20
Simplify the expression
More Steps

Evaluate
20
Write the expression as a product where the root of one of the factors can be evaluated
4×5
Write the number in exponential form with the base of 2
22×5
The root of a product is equal to the product of the roots of each factor
22×5
Reduce the index of the radical and exponent with 2
25
x=±25
Separate the equation into 2 possible cases
x=25x=−25
Determine the test intervals using the critical values
x<−25−25<x<25x>25
Choose a value form each interval
x1=−5x2=0x3=5
To determine if x<−25 is the solution to the inequality,test if the chosen value x=−5 satisfies the initial inequality
More Steps

Evaluate
(−5)2<20
Calculate
52<20
Calculate
25<20
Check the inequality
false
x<−25 is not a solutionx2=0x3=5
To determine if −25<x<25 is the solution to the inequality,test if the chosen value x=0 satisfies the initial inequality
More Steps

Evaluate
02<20
Calculate
0<20
Check the inequality
true
x<−25 is not a solution−25<x<25 is the solutionx3=5
To determine if x>25 is the solution to the inequality,test if the chosen value x=5 satisfies the initial inequality
More Steps

Evaluate
52<20
Calculate
25<20
Check the inequality
false
x<−25 is not a solution−25<x<25 is the solutionx>25 is not a solution
Solution
−25<x<25
Alternative Form
x∈(−25,25)
Show Solution
