Answer:
x1 = -4
x2 = 3
Step-by-step explanation:
[tex]x^{2} + x = 12\\x^{2} +x-12=0\\x^{2} +4x-3x-12=0\\x*(x+4)-3(x+4)=0\\(x+4)*(x-3)=0\\x+4= 0 \\x-3=0\\x=-4 \\x=3\\x1=-4 \\x2=3[/tex]
=> x² + x = 12
=> x² + x -12 = 0
=> x² + 4x - 3x -12 = 0
=> x ( x + 4)-3(x + 4) = 0
=> ( x + 4)(x-3)=0
=> x = 3 , -4
