x 45 44 43 42 41 40 y=50 60 70 80 90 100y与x的关系式

请解答方程组：（39）2x+y=5 (40)x+y=7 (41)2x+3y=12 (42)2x+y=3ax+3y=7 2x-y=8 3x+4y=17 3x-5y=11(43)3x+y=82 (44)3(x-1)=y+5 45 x/4+y/3=7 (46)x+y/3 +x-y/2=610x-11y=87 5(y-1)=3(x+5) 2/3x+y/2=14 3(x+y-)2(x-y)=28 1、x+2+3x=42、 2x+2(x-1)=3/43、 x+2.5=2x-1 3/44、（x-2+3x）/0.5=45、5x=4（x+2） x 45 44 43 42 41 40 y=50 60 70 80 90 100y与x的关系式 matlab中a=[x(11)/x,x(12)/x;x(21)/x,x(22)/x;x(31)/x,x(32)/x;x(41)/x,x(42)/x;x(51)/x,x(52)/x]咋错了 40x+45x 125-x 5175 解方程 x+20%x= x-45%x= 75%x+43%x= 60+2x=185 7x+22=43 16+8x=40 4x-54=14 0.5x-1.2×5=3.8 （x+3）÷2=10.5 6x+4×6=72 5x-16.5×3=25 x+4.8x=29 12.5x-0.9x=52.2 6x+9x-12x=2.37 8x-6=70 12x+48=132 4x+8x=14.4 5.8x-1.6x=12.6 3x+2x×12=42 6（2x-6）=12.6.... 对数y = -0.4589Ln(x) + 9.0657线性y = -0.0591x + 9.0115 R2 = 0.0228多项式y = -0.0029x2 + 0.0593x + 8.1826R2 = 0.0286乘幂y = 7.7454x-0.0888R2 = 0.0089指数y = 7.3001e-0.0091xR2 = 0.0166当X=41,42,43,44,45时Y分别等于什么?具体解法是 解方程21%=42 45%x-20%x=200 x-40%=360 5分之x+x=360 (16x-13)/(4x-3)-(20x-24)/(4x-5)=(32x-30)/(8x-7)-(40x-43)/(8x-9)求x 80到 解方程不是应用题 3X+5X=48 14X-8X=12 6*5+2X=44 20X-50=50 28+6X=88 32-22X=10 24-3X=3 10X*（5+1）=60 99X=100-X X+3=18 X-6=12 56-2X=20 4y+2=6 x+32=76 3x+6=18 16+8x=40 2x-8=8 4x-3*9=29 8x-3x=105 x-6*5=42 x+5=7 2x+3=10 12x-9x=9 6x+18=48 56x 解分式方程：1/X-2+1/X-6=1/X-7+1/X-11/X-2+1/X-6=1/X-7+1/X-11/(x-2)-1/(x-1)=1/(x-7)-1/(x-6)(x-1-x+2)/(x-2)(x-1)=(x-6-x+7)/(x-7)(x-6)1/(x-2)(x-1)=1/(x-7)(x-6)(x-2)(x-1)=(x-7)(x-6)x^2-3x+2=x^2-13x+4213x-3x=42-210x=40x=4 为什么要移向才能解 解一元一次方程（要有过程）3X+5X=48 14X-8X=12 6*5+2X=44 20X-50=50 28+6X=88 32-22X=10 24-3X=3 10X*（5+1）=60 99X=100-X X+3=18 X-6=12 56-2X=20 4y+2=6 x+32=76 3x+6=18 16+8x=40 2x-8=8 4x-3*9=29 8x-3x=105 x-6*5=42 x+5=7 2x+3=10 12x-9x=9 6x+1 x的平方+40x-41 因式分解 x²+40x-41因式分解 40%X+18%X=45 X=? 40x等于45x,那么x等于多少 X减40%X等于42 怎解?