Question

What is the area of a figure
3cm 7cm 7cm

Answer 1

10.26 is the answer for the questiom

Answer 2

`\large\boxed{A=(3√(187))/(4)\ cm^2\approx10.26\ cm^2}`

Explanation:

It's the isosceles triangle (look at the picture).

The formula of an area of a triangle:

`A=(bh)/(2)`

b - base

h - height

Use the Pythagorean theorem to calculate the height:

`1.5^2+h^2=7^2\\\\2.25+h^2=49\qquad\text{subtract 2.25 from both sides}\\\\h^2=46.75\to h=√(46.75)\\\\h=\sqrt{(4675)/(100)}\\\\h=(√(4675))/(√(100))\\\\h=(√(25\cdot187))/(10)\\\\h=(√(25)\cdot√(187))/(10)\\\\h=(5√(187))/(10)\\\\h=(√(187))/(2)\ cm`

We have:

`b=3cm,\ h=(√(187))/(2)\ cm`

Substitute:

`A=(3\cdot(√(187))/(2))/(2)=(3√(187))/(4)\ cm^2`