Question

Simplique as expressões algebricas:
A) 5x (x-1) + 2(x+1)=
b) -2 (2x+1) + 5 (2x-10)=,
c) 2/5 (3x+2)-3/2 (4x+2)=

Answer 1

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

b)-2(2x+1)+5(2x+10)=0
-4x-2+10x-50=0
6x-52=0

c)6x/5 + 4/5 -12x/2 - 6/2=0
1,2x + 0,8 -6x -3=0
-4,8x -2,2 = 0

Answer 2

a)
$5x(x-1)+2(x+1)=0\\ 5x^2-5x+2x+2=0\\ 5x^2-3x+2=0\\ \\ \Delta=(-3)^2-4.5.2=9-80=-71\\ \\ Logo: \ S=\{ \ \ \ \}$

b)
$-2(2x+1)+5(2x-10)=\\ -4x-2+10x-50=0\\ -4x+10x=50+2\\ 6x=52\\ x=\frac{52}{6}=\frac{26}{3}$

c)
$\frac{2}{5}(3x+2)-\frac{3}{2}(4x+2)=0\\ \\ 4(3x+2)-15(4x+2)=0\\ \\ 12x+8-60x+30=0\\ \\ -48x=-38\\ \\ x=\frac{38}{48}=\frac{19}{24}$