Bonjour Lecindy14502
[tex]a=-2\ ;\ b=4\ ;\ c=-5\\\\a)\ 3a-6ab = 3(-2)-6(-2)(4)\\3a-6ab = 3\times(-2)-6\times(-2)\times4\\3a-6ab = -6+48\\\boxed{3a-6ab = 42}\\\\b)\ (a+c)-(a-b)=((-2)+(-5))-((-2)-(4))\\(a+c)-(a-b)=(-2-5)-(-2-4)\\(a+c)-(a-b)=(-7)-(-6)\\(a+c)-(a-b)=-7+6\\\boxed{(a+c)-(a-b)=-1}[/tex]
[tex]c)\ -a+3(a-c)+c^2-ac^2\\=-(-2)+3((-2)-(-5))+(-5)^2-(-2)(-5)^2\\=+2+3\times(-2+5)+25-(-2)\times25\\=2+3\times3+25+2\times25\\=2+9+25+50\\=86\\\boxed{ -a+3(a-c)+c^2-ac^2=86}[/tex]
[tex]d)\ -5ac+3ab-4c=-5(-2)(-5)+3(-2)(4)-4(-5)\\-5ac+3ab-4c=-5\times(-2)\times(-5)+3\times(-2)\times4-4\times(-5)\\-5ac+3ab-4c=10\times(-5)-6\times4+20\\-5ac+3ab-4c=-50-24+20\\\boxed{-5ac+3ab-4c=-54}[/tex]
[tex]e)\ -2(ab)^2-3(a-c)=-2((-2)(4))^2-3((-2)-(-5))\\ -2(ab)^2-3(a-c)=-2\times((-2)\times4)^2-3\times(-2+5)\\ -2(ab)^2-3(a-c)=-2\times(-8)^2-3\times3\\ -2(ab)^2-3(a-c)=-2\times64-3\times3\\ -2(ab)^2-3(a-c)=-128-9\\ \boxed{-2(ab)^2-3(a-c)=-137}\\\\f)\-4ac+2a-(a-b-c)=-4(-2)(-5)+2(-2)-((-2)-(4)-(-5))\\-4ac+2a-(a-b-c)=-4\times(-2)\times(-5)+2\times(-2)-(-2-4+5)\\-4ac+2a-(a-b-c)=-4\times10-4-(-1)\\-4ac+2a-(a-b-c)=-40-4+1\\\boxed{-4ac+2a-(a-b-c)=-43}[/tex]
[tex]g)\ -abc-2ac-3b=-(-2)(4)(-5)-2(-2)(-5)-3(4)\\-abc-2ac-3b=-(-2)\times4\times(-5)-2\times(-2)\times(-5)-3\times4\\-abc-2ac-3b=2\times4\times(-5)-2\times10-12\\-abc-2ac-3b=8\times(-5)-20-12\\-abc-2ac-3b=-40-20-12\\\boxed{-abc-2ac-3b=-72}[/tex]
[tex]h)\ 3(-a+b)-(-a-c)^2=3(-(-2)+(4))-(-(-2)-(-5))^2\\3(-a+b)-(-a-c)^2=3\times(2+4)-(+2+5)^2\\3(-a+b)-(-a-c)^2=3\times6-7^2\\3(-a+b)-(-a-c)^2=18-49\\\boxed{3(-a+b)-(-a-c)^2=-31}[/tex]
