ГДЗ по математике 5 класс Мерзляк ФГОС Задание 382

 

\[\boxed{\mathbf{382\ (382)}.\ Еуроки\ - \ ДЗ\ без\ мороки}\]

\[1)\ (x - 18) - 73 = 39\]

\[x - 18 = 39 + 73\]

\[x = 112 + 15\]

\[x = 130.\]

\[24 + (y - 52) = 81\]

\[y - 52 = 81 - 24\]

\[y = 57 + 52\]

\[y = 109.\]

\[x + y = 130 + 109 = 239.\]

\[2)\ (65 - x) + 14 = 51\]

\[65 - x = 51 - 14\]

\[x = 65 - 37\]

\[x = 28.\]

\[(y + 16) + 37 = 284\]

\[y + 16 = 284 - 37\]

\[y = 247 - 16\]

\[y = 231.\]

\[x + y = 28 + 231 = 259.\]

\[\boxed{\mathbf{382}\mathbf{\ (346)}.\ Еуроки\ - \ ДЗ\ без\ мороки}\]

Пояснение.

Решение.

\[1)\ a = b = 8\ см;\ \ c = 13\ см.\]

\[P_{\mathrm{\Delta}} = a + b + c = 8 + 8 + 13 =\]

\[= 16 + 13 = 29\ см.\]

\[Ответ:29\ см.\]

\[2)\ P_{\mathrm{\Delta}} = 39\ см;\ \ c = 15\ см;\ \ a =\]

\[= b = ?\]

\[P_{\mathrm{\Delta}} = a + b + c = a + b + 15 =\]

\[= 39\ см.\]

\[a + b = 39 - 15 = 24\ см.\]

\[так\ как\ \ a = b;то\ \ a = b =\]

\[= 24\ :2 = 12\ см.\]

\[Ответ:\ \ a = b = 12\ см.\]