Square both sides: Square both sides of the equation to eliminate the square root.(2x+1)2=(x+2)2
Expand using FOIL method: Expand the left side of the equation using the FOIL method (First, Outer, Inner, Last).(2x+1)(2x+1)=x+24x2+2x+2x+1=x+2
Combine like terms: Combine like terms on the left side of the equation. 4x2+4x+1=x+2
Subtract x from both sides: Subtract x from both sides of the equation to bring all x terms to one side.4x2+4x+1−x=x+2−x4x2+3x+1=2
Subtract 2 from both sides: Subtract 2 from both sides of the equation to set the equation to zero.4x2+3x+1−2=04x2+3x−1=0
Quadratic equation: Now we have a quadratic equation. We can either factor it, complete the square, or use the quadratic formula to solve for x. The quadratic formula is x=2a−b±b2−4ac. For this equation, a=4, b=3, and c=−1.
Calculate discriminant: Calculate the discriminant b2−4ac to determine if there are real solutions.Discriminant = 32−4(4)(−1)Discriminant = 9−(−16)Discriminant = 9+16Discriminant = 25
Use quadratic formula: Since the discriminant is positive, there are two real solutions. Use the quadratic formula to find the values of x.x=2⋅4−3±25x=8−3±5
Calculate possible values for x: Calculate the two possible values for x.x=8−3+5 or x=8−3−5x=82 or x=8−8x=41 or x=−1
Check solutions in original equation: We need to check both solutions in the original equation to ensure they do not result in taking the square root of a negative number.Check x=41:2(41)+1=41+221+1=2.251.5=1.5 (True)Check x=−1:2(−1)+1=−1+2−2+1=1−1=1 (False)