(x+30)/(5x-30)=3/5 怎么解这个方程

x-2/5x-(x-2/5x)2/3-(2/5x-1/3x)=30求x x-[2/5x+(x-2/5x-36)*2/3+36]=30 求x (16x-13)/(4x-3)-(20x-24)/(4x-5)=(32x-30)/(8x-7)-(40x-43)/(8x-9)求x 用递归法求y=x-(x*x*x/3!)+(x*x*x*x*x/5!)-(x*x*x*x*x*x*x/7!)+. 30(x+5)=26x+10x(x+5) 5/8X-30+3/10X+84=X x - 3/5x = 240 - 30 - x 求x^2-3x/x^2-6x+9*x^2-11x+30/x^2-5x-1 3x+5(30-x)=126 x-30%-10=3/5x (5x-30):3x=2: (30-x)/(40-x)=3/5 3/5*(40-x)=30-x 5X+6(X+10)+10(X+30)+6(X+70)+3(X+150)=2730,X等于多少 （16x-13)/(4x-3)+（40x-43)/(8x-9)=（32x-30)/(8x-7)+（20x-24)/(4x-5).... （16x-13)/(4x-3)+（40x-43)/(8x-9)=（32x-30)/(8x-7)+（20x-24)/(4x-5) 60％x+25=40 x+30％x=52 19-120％x=7 4分之3x-5％x=17.5 x-10％x=18 （1-25％）x=36 2x+30％x=9.2 一道代数数学题,积分30,条件充分性判断：多项式f(x)=3x^3 - 11x*x - 23x - 9的值是 -5(1)x*x - 1 = 5x (2)x*x - 1 = 3x