Algebra
Calculus
Trigonometry
Matrix
Question
Simplify the expression
20x2−9
Evaluate
5x2×4−9
Solution
20x2−9
Show Solution
Find the roots
x1=−1035,x2=1035
Alternative Form
x1≈−0.67082,x2≈0.67082
Evaluate
5x2×4−9
To find the roots of the expression,set the expression equal to 0
5x2×4−9=0
Multiply the terms
20x2−9=0
Move the constant to the right-hand side and change its sign
20x2=0+9
Removing 0 doesn't change the value,so remove it from the expression
20x2=9
Divide both sides
2020x2=209
Divide the numbers
x2=209
Take the root of both sides of the equation and remember to use both positive and negative roots
x=±209
Simplify the expression
More Steps
Evaluate
209
To take a root of a fraction,take the root of the numerator and denominator separately
209
Simplify the radical expression
More Steps
Evaluate
9
Write the number in exponential form with the base of 3
32
Reduce the index of the radical and exponent with 2
3
203
Simplify the radical 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
253
Multiply by the Conjugate
25×535
Multiply the numbers
More Steps
Evaluate
25×5
When a square root of an expression is multiplied by itself,the result is that expression
2×5
Multiply the terms
10
1035
x=±1035
Separate the equation into 2 possible cases
x=1035x=−1035
Solution
x1=−1035,x2=1035
Alternative Form
x1≈−0.67082,x2≈0.67082
Show Solution