Question

pls solve this both the questions correctly
please

I'll mark him/her as brainliest​

Answer 1

Step-by-step explanation:

semi peri.= (a+b+c)/2

s = (8+10+10)/2

s = 28/2

s = 14

area of ∆= √s(s-a)(s-b)(s-c)

= √14(14-8)(14-10)(14-10)

= √14×6×4×4

= √2×7×2×3×4×4

=4×2√7×3

= 8√21

rate of 1cm²= 120

rate of 8√21 trangular plot= 120×8√21

rate of trangular plot= 960√21

Q)area of base =πr²=192

area of cylinder= πr²h

= 192×h

= 192×10

= 1920

#666

Answer 2

1.] Correct Question:-

• Find the Cost of leveling a triangular plot at the rate of Rs. 120 per cm² having sides 8cm, 10cm, 10cm.

Given:-

• 1st side = 8cm
• 2nd side = 10cm
• 3rd side = 10cm
• Cost of leveling it per cm² = Rs. 120

To find:-

• Cost of leveling it

Formula to be used:-

$\underline\red{\boxed{\bf Ar.(∆) = √s(s-a)(s-b)(s-c)}}$

Solution:-

Semi-perimeter (S) = $\bf\dfrac{a+b+c}{2}$

S = $\bf\dfrac{8+10+10}{2}$

S = $\bf\dfrac{28}{2}=14$

$\bf Ar(∆) = √14(14-8)(14-10)(14-10)$

$\bf Ar (∆) = √14×6×4×4$

$\bf Ar (∆) = √7×2×2×3×2×2×2×2$

$\bf Ar (∆) = 2×2×2√7×3$

$\bf Ar (∆) = 8√21cm²$

Hence, Cost of the plot = 8√21 × 120 = 960√21 Rs.

2.] Correct Question:-

• Find the volume of a pipe which is in the form of a cylinder having base area 192cm² and length of the pipe is 10cm

Given:-

• base area = 192cm²
• length (height) = 10cm

To find:-

• volume of this pipe

Formula:-

$\underline\pink{\boxed{\bf Volume\:of\: cylinder = 2πrh}}$

In the question we are already provided with the base area = 192cm² = 2πr

Solution:-

$\bf Volume = 192 × 10$

$\bf Volume = 1920 cm³$

hence, 1920 cm³ is the required answer