Justify each step of the proof. Conjecture: If 2(x^2+5)=60, then x is 5, or -5.
1. 2(x^2 + 5) = 60
2. 2x^2 + 10 = 60
3. 2x^2 = 50
4. x^2 = 25
5. x

Justify each step of the proof. Conjecture: If 2(x^2+5)=60, then x is 5, or -5.
1. 2(x^2 + 5) = 60
2. 2x^2 + 10 = 60
3. 2x^2 = 50
4. x^2 = 25
5. x

Looks like yuo're just missing step 5:
x = \sqrt {25} = \pm 5