Solve by completing the square

Solve By Completing The Square class=

Sagot :

[tex]\qquad\qquad\huge\underline{{\sf Answer}}☂[/tex]

Let's solve ~

[tex]\qquad \sf  \dashrightarrow \: {x}^{2} + 8x = 33 [/tex]

[tex]\qquad \sf  \dashrightarrow \: {x}^{2} + 8x +16 = 33 + 16 [/tex]

[tex]\qquad \sf  \dashrightarrow \: (x + 4) {}^{2} = 49[/tex]

[tex]\qquad \sf  \dashrightarrow \: x + 4 = \sqrt{49} [/tex]

[tex]\qquad \sf  \dashrightarrow \: x + 4 = \pm7[/tex]

Hence, there are two solutions ~

  • 1. when x + 4 = 7

[tex]\qquad \sf  \dashrightarrow \: x + 4 = 7[/tex]

[tex]\qquad \sf  \dashrightarrow \: x = 7 - 4[/tex]

[tex]\qquad \sf  \dashrightarrow \: x = 3[/tex]

  • 2. when x + 4 = -7

[tex]\qquad \sf  \dashrightarrow \: x + 4 = - 7[/tex]

[tex]\qquad \sf  \dashrightarrow \: x = - 7 - 4[/tex]

[tex]\qquad \sf  \dashrightarrow \: x = - 11[/tex]

I hope you understood ~