Question

who to solve perimeter

of b and e​

Answer 1

Answer:

Step-by-step explanation:

Answer 2

Answer:

Finding the missing sides in the following figures.

★ Question (b) :

• ➝ Perimeter = 30 cm
• ➝ Breadth = 3 cm.

Here we have given that the perimeter and breadth of rectangle are 30 cm and 3 cm. We need to find the lenght of rectangle. So, we'll find the lenght by using perimeter of rectangle formula :

$\begin{gathered} \qquad{\dashrightarrow{\sf{Perimeter = 2(Lenght + Breadth)}}}\\\\\quad{\dashrightarrow{\sf{30 \: cm= 2(Lenght + 3)}}} \\ \\ \quad{\dashrightarrow{\sf{\dfrac{30}{2} = (Lenght + 3)}}} \\ \\ \quad{\dashrightarrow{\sf{\cancel{\dfrac{30}{2}} = (Lenght + 3)}}} \\ \\ \quad{\dashrightarrow{\sf{15 = (Lenght + 3)}}} \\ \\ \quad{\dashrightarrow{\sf{Lenght = 15 - 3}}} \\ \\ \quad{\dashrightarrow{\sf{Lenght =12 \: cm}}} \\ \\ \quad\bigstar{\underline{\boxed{\frak{\pink{Lenght =12 \: cm}}}}}\end{gathered}$

• Hence, the lenght of rectangle is 12 cm.

$\begin{gathered}\end{gathered}$

★ Question (e)

• ➝ Perimeter = 150 cm
• ➝ Lenght = 60 cm

Here we have given that the perimeter and lenght of rectangle are 150 cm and 60 cm. We need to find the breadth of rectangle. So, we'll find the breadth by using perimeter of rectangle formula :

$\begin{gathered} \qquad{\dashrightarrow{\sf{Perimeter = 2(Lenght + Breadth)}}} \\\\{\dashrightarrow{\sf{150 \: cm= 2(60 + Breadth)}}} \\ \\ {\dashrightarrow{\sf{\dfrac{150}{2} = (60 + Breadth)}}} \\ \\ \quad{\dashrightarrow{\sf{\cancel{\dfrac{150}{2}} = (60 + Breadth)}}} \\ \\ \quad{\dashrightarrow{\sf{75 = (Breadth + 60)}}} \\ \\ {\dashrightarrow{\sf{Breadth = 75 - 60}}} \\ \\ {\dashrightarrow{\sf{Breadth =15 \: cm}}} \\ \\ \bigstar{\underline{\boxed{\frak{\pink{Breadth =15 \: cm}}}}}\end{gathered}$

• Hence, the breadth of rectangle is 15 cm.

$\begin{gathered}\end{gathered}$

Learn More :

$\begin{gathered}\begin{gathered} \boxed{\begin{array}{l}\\ \large\dag\quad\underline{\bf Formulas\:of\:Areas:-}\\ \\ \star \: \: \sf Circle = \pi r^2 \\ \\ \star \: \; \sf Square=(side)^2\\ \\ \star\; \; \sf Rectangle=Length\times Breadth \\\\ \star \: \: \sf Triangle=\dfrac{1}{2}\times Breadth\times Height \\\\ \star \: \: \sf Scalene\triangle=\sqrt {s (s-a)(s-b)(s-c)}\\ \\ \star \: \: \sf Rhombus =\dfrac {1}{2}\times d_1\times d_2 \\\\ \star \: \: \sf Rhombus =\:\dfrac {1}{2}p\sqrt {4a^2-p^2}\\ \\ \star \: \: \sf Parallelogram =Breadth\times Height\\\\ \star \: \: \sf Trapezium =\dfrac {1}{2}(a+b)\times Height \\ \\ \star \: \: \sf Equilateral\:Triangle=\dfrac {\sqrt{3}}{4}(side)^2\end {array}}\end{gathered}\end{gathered}$

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