Question

Raspunsurile , va rog?!.

Answer 1

1) 90grade-48grade35'29''=89grade59'60''-48grade35'29''=(89grade-48grade)+(59'-35')+(60''-29')=41grade24'31''
2)
I-----------I---------------------I--------------------I
A         O                    P                   B
OA=20cm
OP=30cm
AP=OA+OP=20+30=50 CM
P este mijlocul lui AB atunci AP=PB=AB/2
50=AB/2⇒AB=2x50=100cm
OP=AB-OA=100cm-20 cm=80cm
3)este 0
5)
(x+1)/2=6/4
4(x+1)=6·2
4x+4=12
4x=12-4
4x=8
x=8/4=2
6)
0,4+0,1-0,25=0,5-0,25=0,25
7)
AOB+BOC=180grade
BOC=180-65=115 grade
8)
0,1(3)=(13-1)/90=12/90 simplif.cu 2=6/45 simplif cu 3=2/15
3,(8)=(38-3)/9=35/9
2/15+35/9=(2x9+35x15)/135=(18+525)/135=543/135=4,0(2)
9)
AOB+BOC=90 grade
AOB=90grade-AOB=90-66=24 grade
EOB==AOB/2=24/2=12grade
EOC=EOB+BOC
EOC=12+66=78grade
10)a)
{a,b}dp{2,4}
2a=4b=k
2a=k⇒a=k/2
4b=k⇒b=k/4
(2a+3b)(a+4b)=?
(2·k/2+3·k/4)/(k/2+4·k/4)=
(k+3k/4)/(k/2+k)=
(4k+3k)/4:(k+2k)/2
7k/4·2/3k=7/6
(2a+3b)(a+4b)=7/6
b)
(6x+7)/(7x+2)
conditia 7x+2≠0⇒x≈-2/7
6x+7=0
6x=-7
x=-7/6
x=-1,1(6)
11)I------------I-----------I------------I
    D          A           C           E
AC=6cm
AC=AD=DC/2
6=DC/2⇒DC=6·2=12cm
EC=DC/4=12/4=3cm
AD=AC=6cm
AE=AC+EC=6+3=9cm