2x²+5=13

How do you find the value of x?

2x²+5=13

subtract the 5 on both sides

2x²=8

divide by 2 on both sides

x²=4

put each side under the radical because of the exponent 2

√x²=√4

the radical cancels out the exponent 2; √4 = 2

x=2

Since 5 does not contain the variable to solve for, move it to the right-hand side of the equation by subtracting 5 from both sides.

2 x^2 = - 5 + 13

Add - 5 and 13 to get 8.

2 x^2 = 8

Divide each term in the equation by 2.

x^2 = 4

Take the square root of both sides of the equation to eliminate the exponent on the left-hand side.

x=± √4

Rewrite 4 as 2^2

x=± √ 2^2

Pull terms out from under the radical.

x=±2

First, use the positive value of the ± to find the first solution.

x=2

Next, use the negative value of the ± to find the second solution.

x=-2

x=2,-2