{25x+28(80-x)≥2090 25x+28（80-x)≤2098}的解集

{25x+28(80-x)≥2090 25x+28（80-x)≤2098}的解集 2090小于等于28X+28(80-X)小于等于2096咋解题错 25X+28(80-X) [1].x-16.4=80 [2]28-2x=13 [3]3x+2x=25 [4]32-2x=30 [5] [x+5]*8=320 [6]x-2分之1x=2 计算:(x^2 - 3x - 28)/(x^2 + 5 - 6x) / (3x+12)/(x^3 - 10x^2 + 25x) [1].x-16.4=80 [2]28-2x=13 [3]3x+2x=25 [4]32-2x=30 [5] [x+5]*8=320 [6]x-2分之1x=2[1].x-16.4=80 [2]28-2x=13 [3]3x+2x=25 [4]32-2x=30 [5] [x+5]*8=320 [6]x-2分之1x=2 f(x)分段函数-x^2+x(x≥0),x^2+x(x x-2x+3x-4x+5x.+99x-100x=25求解 4.2-0.6x=3.6x 5x+2x=33.6 7x-4x=0.75 2x+7x+2.1=12 56x-32x-119=361 x+5=2x 3x+9=6x 4x-28=2x 2x+18=7x 5x=25*4-15x 7x-x+2*3=29.4 (28.8+5.5x+3.2）除2=71 x-25=80%x,x=? (x+5)(x^2-5x+25) x X 2x=25 x^2/x-5+25/5-x |x-2|(3x²-5x-28)/(x+3)≥0解不等式 数学题啊!解不等式（过程）4x-2≥5x+7x+15>2x-36（x+2)≤3x-15（x+2)≤6x+13x-1≥6x-25(x+2)3x+20x-5/4 +1≤6x-23x+4>x/2 -1 解方程:65%x-40%x=80 x-6%x=282 x+70%x=68 15%x+20=65%x-40%x=80x-6%x=282x+70%x=6815%x+20=8030%x-28=623X15-20%x=25 x/x^2-25-5/x^2+10x+25 (x^+x)^2-10(x^2+x)+25 2x=25+x.