設(shè)l'為y=kx+b
∵l'與直線l：3x+4y-12=垂直,
∴l(xiāng)'的斜率k=-4/3
∴直線l'為：y=-4x/3+b
又當(dāng)x=0時(shí),y=IbI；當(dāng)y=0時(shí),x=3IbI/4
S=(3IbI/4)*IbI/2=4
b^2=8/3
∴b=±2√6/3
∴直線l'為：y=-（4x/3）+2√6/3,y=-(4x/3)-2√6/3