Question

(5,25-0,63:1,4)*0,4 3,2x+0,8=12 решите уравнения петр шел к озеру 0,7ч по одной дороге , а возвращался по другой дороге 0,8ч , пройдя всего 6,44км . С кокой скоростью шел петр к озеру если возвращался он со скоростью 3,5кмч

Answer 1

Ответ:

Пошаговое объяснение:

(5,25-0,63:1,4)*0,4  = (5,25 - 0,45) * 0,4 = 4,8 * 0,4 = 1,92

3,2x+0,8=12

3,2x = 12 - 0,8

3,2x = 11,2

x = 11,2 : 3,2

x = 3,5

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3,5 * 0,8 = 2,8км длина дороги от озера до дома

6,44 - 2,8 = 3,64км длина дороги от дома до озера

3,64 : 0,7 = 5,2км/ч с такой скоростью шел Петр к озеру

Answer 2

To solve the first equation:

(5.25 - 0.63 : 1.4) * 0.4

Let's break it down step by step:

1. First, perform the division: 0.63 / 1.4 = 0.45
2. Then subtract from 5.25: 5.25 - 0.45 = 4.80
3. Finally, multiply by 0.4: 4.80 * 0.4 = 1.92

So, the solution to the first equation is 1.92.

Now, let's solve the second equation:

3.2x + 0.8 = 12

To isolate x, we need to move 0.8 to the other side of the equation:

3.2x = 12 - 0.8 3.2x = 11.2

Now, divide both sides by 3.2 to solve for x:

x = 11.2 / 3.2 x = 3.5

So, the solution to the second equation is x = 3.5.

Now, let's calculate the speed at which Peter walked to the lake:

We know that time = distance / speed.

Let the speed at which Peter walked to the lake be v km/h.

Time taken to walk to the lake = 0.7 hours.

Distance to the lake = 6.44 km.

So, we can write the equation:

0.7 hours = 6.44 km / v km/h

Now, let's solve for v:

v = 6.44 km / 0.7 hours v ≈ 9.2 km/h

Therefore, Peter walked to the lake at a speed of approximately 9.2 km/h.