3\10, 6/7, 1/3 9/5; 5-ое 9/10, 2/11, 15/8, 3/20.
(x-2)(x-2)+4x=13
x^2-2x-2x+4+4x=13
x^2+4=13
x^2=9
x=√9
x1=-3
x2=3
1)6*5=30-все рулоны
2)30*235=7025 рэ
(77+23+35)-50= 100+35-500=(100-50)+35=50+35 =85
1) 6 7/9 - 3 22/27 = 61/9 - 103/27 = 183/27 - 103/27 = 80/27 = 2 26/27
4) 8 13/20 - 5 27/40 = 173/20 - 227/40 = 346/40 - 227/40 = 119/40 = 2 39/40 = 2.975