Question

Find tha area of triangle.Whose area are 5cm 7 cm 9 cm

Answer 1

Step-by-step explanation:

area sum of triangle is 180cm

the the ratios were 5x,7x,9x

5x+7x+9x=21x

21x=180

x=180/21

x=8.571

5x=8.571x5=42.857

7x=8.571x7=60

9x=8.571x9=77.142

I think the question is wrong so It will help I hope so

Answer 2

》Right Question:

[Q]Find area of triangle whose sides are 5cm,7cm and 9cm?

Answer:

$\huge{\pink{\green{\sf{{\green{\therefore Area = \frac{21 \sqrt{11} }{4} {cm}^{2}}}}}}}$

Step-by-step explanation:

$\huge{\pink{\green{\underline{\red{\sf{SOLUTION-}}}}}}$

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: { \orange{ \underline{given}}} \\ { \green{Side \: of \: triangle \: are \: 5,7\:and\:9}} \\ \\ \: \: \: \: \: \: \: \: { \red{ \underline{to \: find : }}} \\ { \purple{Area \: of \: triangle =? }}$

• In question we have information of all sides of triangle.

• So we use herons formula to find area of triangle

• According to given question:

$\to S = \frac{a + b + c}{2} \\ \to S = \frac{5 + 7 + 9}{2} \\ \to S= \frac{21}{2} \\ \\ \to according \: to \: herons \: formula = \sqrt{S(S - a)(S - b)(S - c)} \\ \to Area = \sqrt{ \frac{21}{2}( \frac{21}{2} - 5)( \frac{21}{2} - 7)( \frac{21}{2} - 9) } \\ \to Area = \sqrt{ \frac{21}{2} ( \frac{21 - 10}{2})( \frac{21 - 14}{2} )( \frac{21 - 18}{2}) } \\ \to Area = \sqrt{ \frac{21}{2}( \frac{11}{2})( \frac{7}{2})( \frac{3}{2} )} \\ \to Area = \sqrt{ \frac{21 \times 11 \times 7 \times 3}{2 \times 2 \times 2 \times 2} } \\ \to Area = \sqrt{ \frac{3 \times 7 \times 11 \times 7 \times 3}{2 \times 2 \times 2 \times 2 } } \\ \to Area = \frac{7 \times 3 \sqrt{11} }{2 \times 2} \\ {\green{\therefore Area = \frac{21 \sqrt{11} }{4} {cm}^{2}}}$