Answer:
Third side is 15cm. Perimeter is 37cm.
Step-by-step explanation:
In a triangle sum of two sides is always greater than third side. Two sides of a isosceles triangle are equal.
So if the third side is 7cm
7+7=14cm which is less than 15 cm.
hence third side is 15 cm as
15+15=30cm which is greater than 7cm
15+7=22cm which is greater than 12cm
then
perimeter=15+7+15=37cm
Knowing the squareroot of 81 is 9, we can easily know that square root of 83 is close to 9.
9 to the closest tenth is 10.
Hope I helped :)
Answer:
290 centimetres
Step-by-step explanation:
The ratio of the length of the pieces of wood is 6 : 10 : 12.
We have to find the total ratio first:
6 + 10 + 12 = 28
The longer piece of wood has ratio 10.
The length of the original wooden plank is 812 centimetres, therefore, the length of the longer piece of wood is:
10/28 * 812 = 290 centimetres
