Question

a) find x -photo is attached, best answer will be marked brainliest, nonsense will be reported, thank you!

Answer 1

Answer:

x=12

Step-by-step explanation:

area of four triangles =

$4 \times (1 \div 2) \times 2x \times x$

$= 4x {}^{2}$

area of base =

$x \times x = x {}^{2}$

therefore

$4x {}^{2} + x {}^{2} =720$

$x {}^{2} = 720 \div 5 = 144$

$x = 12$

Answer 2

Gɪᴠᴇɴ :-

• surface Area or square - Based Pyramid = 720cm².
• Square Base Length = x cm.
• slant Height = 2x cm.

Tᴏ Fɪɴᴅ :-

• value of x ?

Fᴏʀᴍᴜʟᴀ ᴜsᴇᴅ :-

Surface Area or square - Based Pyramid with Base as B cm & slant Height as L cm is :- B² + 2BL

Sᴏʟᴜᴛɪᴏɴ :-

we have given That,

→ B = x cm.

→ L = 2x cm.

→ surface Area = 720cm².

Putting All values in Above Told formula we get :-

→ B² + 2BL = 720

→ (x)² + 2 * x * 2x = 720

→ x² + 4x² = 720

→ 5x² = 720

→ x² = 144

→ x² = (12)²

→ x = 12cm. (Ans.)

Hence, value of x or Base of square - Based Pyramid is 12cm.