1) x+x+(x-3)+(x-3)=48
2x+2(x-3)=48
2(x+x-3)=48
2x-3=48./2
2x-3=24
2x=24-3
2x=21
x=21/2
x=10.5
2) 10.5-3=7.5
3) S=10.5*7.5=78.75 (кв. см)
1) x+x+(x-3)+(x-3)=48
2x+2(x-3)=48
2(x+x-3)=48
2x-3=48./2
2x-3=24
2x=24-3
2x=21
x=21/2
x=10.5
2) 10.5-3=7.5
3) S=10.5*7.5=78.75 (кв. см)