Question

Aflatimas unughiului unui patrulater știind ca a) sunt direct proporțională cu 5,7,8,10
B)sunt încă prop cu 0,5; 0(3);0,25;0,1(6)

Answer 1

a)
a/5=b/7=c/8=d/10
b=7a/5
c=8a/5
d=10a/5=2a
a+b+c+d=360°
a+7a/5+8a/5+2a=360°
3a+15a/5=360°
3a+3a=360°
6a=360°
a=360°:6=60°
b=7×60°/5=84°
c=8×60°/5=96°
d=2×60°=120°


b)0,5=1/2   0(3)=3*9=1/3   0,25=25/100=1/4   0,1(6)=(16-1)/90=15/90=1/6
0,5a=a/2
0(3)b=b/3
0,25c=c/4
0,1(6)d=d/6
a/2=b/3=c/4=d/6     b=3a/2    c=4a/2=2a   d=6a/2=3a
a+b+c+d=360°
a+3a/2+2a+3a=360°
6a+3a/2=360°
12a+3a=720°
15a=720°
a=720°:15
a=48°
b=3×48°/2=72°   
c=4×48°/2=96°
d=6×48°/2=144°