*If you need me to do #5, DM me!
3. The area of a triangle can be given by (just plug and chug as always):

The area of the triangle is
6ft².
4. I will divide into a triangle and a rectangle (because the actual equation for the area of a pentagon requires it to be a perfect pentagon). Let's do the triangle first (height is 3 because you subtract 12 from 15):


Now we just add them:

So, the area of that pentagon is
108m².
5. You are actually wrong on this one because the area of a triangle is:

So, just halve your answer and it will be correct.
6. We can just split it into 4 triangles of equal area and then multiply the area of 1 triangle by 4 to get the total area. Let's do just that:

Multiply by 4 to get total area:

So, the area of the given rhombus is
25cm².


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<h2>Given:-</h2>
<h3>perimeter of rectangle=26cm</h3>
<h3>Area of rectangle=>30cm²</h3>
<h3>{•°• perimeter of rectangle=2(l+b) }</h3>
<h3>{•°•. Area of rectangle=lxb}</h3>
<h3>So, 2(l+b)=26</h3><h3> =>(l+b)=26/2</h3><h3> =>l+b=13</h3><h3> =>l=(13-b) ----------(1)</h3>
<h3>Again,</h3>
<h3> =>lxb=30</h3><h3> =>(13-b)xb=30 {putting the value of l from equation 1}</h3><h3> </h3><h3> =>13b-b²=30</h3><h3> =>b²-13b+30=0</h3><h3> =>b²-10b-3b +30=0</h3><h3> =>b(b-10)-3(b-10)=0</h3><h3> =>(b-10)(b-3)=0</h3><h3> </h3><h3>or,</h3>
<h3> =>b=10 or b=3</h3>
<h3>putting the value of b in equation (1)</h3>
<h3> =>l=(13-b)</h3><h3> =>l=13-10=3 { taking b=10}</h3><h3> =>l=13-3=10 { taking b=3}</h3>
<h3>Hence, length=3 when breadth=10</h3><h3> length=10 when breadth=3</h3>
<h3>•take care</h3><h3>°mark as brainlist please</h3><h3>•follow me</h3>
✌️✌️
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Draw arcs on either side of a given point on the line