|3-x|=18

解答

∣ 3 - x ∣ = 18

x = - 15 or x = 21

求解步骤

∣ 3 - x ∣ = 18

使用绝对值运算法则: 若

∣ u ∣ = a, a > 0

，则

u = a

u = - a

3 - x = - 18 or 3 - x = 18

3 - x = - 18 or 3 - x = 18

x = - 15 or x = 21

s im pl i f y 1 - (- 5)

(7 k - 1)^{2} = - 8

f a c t or 4 x^{4} - 7 x^{2} + 3

0.5 x = 1 - x^{2}

f a c t or c d + 5 c + 4 d + 20