(30+3x)乘(30-x)=1092怎么解?
问题描述:
(30+3x)乘(30-x)=1092怎么解?
答
(30+3x)(30-x)= 1092
3 (x+10)(30-x) = 1092
(x+10)(30-x) = 364
x² -20x + 64 = 0
(x-4)(x-16) = 0
x = 4 或 x = 16