1.
a) t(t+x)+11(t+x)=(t+x)(t+11)
b) 2m²(4-m)-(4-m)=
=(4-m)(2m²-1)
2.
18k²-18k+7y-7ky= =18k(k-1)+7y(1-k)= =18k(k-1)-7y(k-1)=
=(k-1)(18k-7y)=
=(1/9-1)(18/9-14/7)=(1/9-9/9)*
*2-2=0
3. (0.7*2.7-1.4*0.7)+(0.3*2.7-1.4*0.3)=0.7(2.7-1.4)+0.3(2.7-1.4)=(2.7-1.4)(0.7+0.3)=1.3*1=1.3
4х²-12х+5=0
D+ (-12)²-4*4*5= 144-80= 64
D>0, 2 корня
х1= -(-12)+√64 / 2*4= 12+8/8= 20/8 = 2,5
х2= -(-12)-√64 /2*4= 12-8/8= 4/8= 0,5
2,5+0,5= 3
(7^8)^3/(7^7)^5=7^12/7^12=1
X-2/3-x/4=2 приводим к общему знаменателю
4(x-2)-3*x=2*6
4x-8-3x=12
x-8=12
x=20
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15y=-30
y=-2
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