Question

bài 1: tính

a) -6x+3(7+2x)

b)15y-5(6x+3y)

c) x(2x+1)-x²(x+2)+(x³-x+3)

d)4(x-6)-x²(2+3x)+x(5x-4)3x²(x-1)

bài 2: tìm x

a)3x+2(5-x)=0

b)3x²-3x(-2+x)=36

c)5x(12x+7)-3x(20x-5)=-100

Answer 1

Nãy giờ gửi 2 cái ảnh mà mãi ko lên 😭😭😭

Answer 2

Answer 3

a,\(-6x+3\left(7+2x\right)=-6x+21+6x=21\)

b,\(15y-5\left(6x+3y\right)=15y-30x-15y=-30x\)

c,\(x\left(2x+1\right)-x^2\left(x+2\right)+x^3-x+3\)

\(=2x^2+x-x^3-2x^2+x^3-x+3=3\)

d,\(4\left(x-6\right)-x^2\left(2+3x\right)+x\left(5x-4\right)+3x^2\left(x-1\right)\)

\(=4x-24-2x^2-3x^3+5x^2-4x+3x^3-3x^2\)

\(=-24\)

Answer 4

a, \(3x+10-2x=0\)

\(< =>x+10=0< =>x=-10\)

b,\(3x^2+6x-3x^2=36\)

\(< =>6x=36< =>x=\frac{36}{6}=6\)

c, \(5x\left(12x+7\right)-3x\left(20x-5\right)=-100\)

\(< =>60x^2+35x-60x^2+15x=-100\)

\(< =>50x=-100< =>x=-\frac{100}{50}=-2\)