Question

Помогите пожалуйста!!!

Answer 1

$a)(5 c^{2} -4c)-(8 c^{2} + 4c-1)= 5c ^{2}-4c-8 c^{2}-4c+1=-3c ^{2} - 8c+1$
$b) 2 x^{2} (6-5x)=12 x^{2} -10 x^{3} \\ 2. a) 6 a^{2} +8ac=2a(3a+4c) \\ b) 10 x^{5} -2 x^{3}=2 x^{3}(5 x^{2} -1) \\ 3. 4(1-3x)=15-10(x+2) \\ 4-12x=15-10x-20 \\ -12x+10x=-5-4 \\ -2x=-9 \\ x=-4,5 \\ 4. s=vt \\ s=4x \\ s=(x-4)*6=6x-24 \\ 6x-24=4x \\ 2x=24 \\ x=12 \\ 6. 0,75= \frac{75}{100} = \frac{3}{4} \\ \frac{3}{4} x^{2} -xy+0,6 y^{2} - \frac{3}{4} x^{2} +xy+0,4 y^{2} -5 \\ y^{2} -5$