7√7
using the ' rule of radicals '
• √a × √b ⇔ √ab
simplifying the radicals
√28 = √(4 × 7 ) = √4 × √7 = 2√7
√63 = √(9 × 7) =√9 × √7 = 3√7
√112 = √(16 × 7 ) = √16 × √7 = 4√7
substituting into the expression
3(2√7) - 5(3√7) + 4(4√7) = 6√7 - 15√7 + 16√7 = 7√7
Answer:

Step-by-step explanation:
we can easily calculate the perimeter of three points, using vectors. See the picture...
Answer:
15+85+x =180
X=180-15-85
X=8O°
Step-by-step explanation:
Answer:
19.10
Step-by-step explanation:
If im correct,
You subtract 10 and 5. Wich is 5. Then multiply that by 3.82.