1 -- I
10 -- X
100 -- C
1000 -- M
Answer:
10.2cm
Step-by-step explanation:
Perimeter is the sum of the lengths of all sides.
1st side: 9cm
2nd side: 7.8cm
Perimeter: 27cm
Perimeter = 1st + 2nd +3rd side of a triangle
27cm = 9cm +7.8cm + 3rd side
3rd side = 27cm - 9cm -7.8cm
= 10.2cm
Isosceles Triangle, has 2 equal sides and angles.
OK for this question you need to find out how many more post are needed. If you look at the diagram it shows that one side is 50 feet. Now there are two sides that will need post, because the barn side need no more. Now if there are two side both 50 feet, and you need a post every ten feet. How many posts are needed?
The length of the brace required is 4.3m
What is sine rule?
In a ΔABC a, b and c are the sides and A, B and C are angles then,

We can find the length, l as shown below:
Let AB=3m, BC=2m and AC=l
Let ∠A=25°
So, in ΔABC




∠C=39.34°
∠A+∠B+∠C=180°
∠B=180°-25°-39.34°
∠B=115.66°



l=4.2659
Rounding to nearest tenth of meter.
l=4.3m
Hence, the length of the brace required is 4.3m
Learn more about Sine Rule here:
brainly.com/question/25852087
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