A painter needs to cover a triangle registration 63m by 66m by 73m .a can of paint covers 70 square m .how many cans will be needed.use herons formula?

First, calculate the semi-perimeter of the triangle using Heron's formula:

s = (a + b + c) / 2
s = (63 + 66 + 73) / 2
s = 202 / 2
s = 101

Next, calculate the area of the triangle using Heron's formula:

Area = √(s * (s - a) * (s - b) * (s - c))
Area = √(101 * (101 - 63) * (101 - 66) * (101 - 73))
Area = √(101 * 38 * 35 * 28)
Area = √(3537800)
Area ≈ 1881.9 square meters

Now, calculate the number of cans needed:

Number of cans = Area / coverage per can
Number of cans = 1881.9 / 70
Number of cans ≈ 26.88

Therefore, the painter will need 27 cans of paint to cover the triangle.

Step 1: Calculate the semiperimeter of the triangle.

```
s = (63 + 66 + 73) / 2 = 101
```

Step 2: Calculate the area of the triangle using Heron's formula.

```
A = √[s(s - 63)(s - 66)(s - 73)]
A = √[101(38)(35)(28)]
A = 2191.9 m²
```

Step 3: Calculate the number of cans needed.

```
Number of cans = Area of triangle / Area covered by 1 can
Number of cans = 2191.9 m² / 70 m²
Number of cans = 31.31
```

Since we can't buy a fraction of a can, we round up to the nearest whole number.

Therefore, 32 cans will be needed.