Sagot :
Réponse :
1) 3x = - 2[5]
3x/3 = - 10/3
x = [tex]\frac{-10}{3}[/tex]
2) 10x - 7 = 28[13]
10x - 7 +7 = 364 +7
10x/10 = 371/10
x = 37.1
3) 4(2x - 1) = x - 8[16]
8x-4+4 = x - 128+4
8x-x= x - 124 -x
7x/7=- 124/7
x=[tex]\frac{-124}{7}[/tex]
4)2 * (x - 5) ^ 2 = 2x ^ 2 + x - 1[11]
2 * ( [tex]x^{2}[/tex]− 1 0 + 2 5) = [tex]4x^{2}[/tex] + x - 11
( [tex]2x^{2}[/tex]−20 +50) = [tex]4x^{2}[/tex] + x - 11
[tex]2x^{2}[/tex]−20 +50-[tex]4x^{2}[/tex]-x = [tex]4x^{2}[/tex] + x - 11-[tex]4x^{2}[/tex]-x
- [tex]2x^{2}[/tex]−21 +50-50=- 11-50
- [tex]2x^{2}[/tex]−21 /-2=- 61/-2
[tex]x^{2}[/tex]-10.5x=30.5
[tex]\sqrt{x^{2} -10.5x}[/tex] = [tex]\sqrt{30.5}[/tex]
x-[tex]\sqrt{-10.5x}[/tex] = [tex]\sqrt{30.5}[/tex]
