Question

Please help me guys this is an emergency I will give you brainliest and points hurry up Thank you! (No.11only)

Answer 1

Answer:

6.75 cm

225.66 cm²

Step-by-step explanation:

V= 1/3lwh= 180

V= 1/3*10*8*h= 80h/3 cm³

• h= 3V/80= 3*180/80= 6.75 cm

Surface area of the pyramid:

A=lw+l√(w/2)²+h²+w√(l/2)²+h²

• A= 10*8+10√(8/2)²+6.75² + 8√(10/2)²+6.75²= 225.66 cm²

Answer 2

Answer:

Step-by-step explanation:

Volume of pyramid = 1

3 × base area × height

180 = 1

3 × 10 × 8 × height

180 = 80

3 × height

Height = 6.75 cm

part two

Let the slant height from V to PQ be l1 cm,

the slant height from V to QR be l2 cm.

Using Pythagoras’ Theorem,

l1 = square root(6.75^2 + 4^2) = 7.846 (to 4 s.f.)

l2 =square root(6.75^2 + 5^2)= 8.400 (to 4 s.f.)

Total surface area of pyramid

Area of all triangular faces + area of square base

2 (1/2*10*7.846+1/2*8*8.400)+10*8

2(39.23 + 33.6) + 80

145.66 + 80

226 cm2 (to 3 s.f.)