It's the first one lmk if you want an explanation
Answer:

Step-by-step explanation:
we have
-----> equation A
-----> equation B
To find out (V of r)(t) substitute equation B in equation A




(1.35)(27)= 36.45(0) = 0 (13) = 13
Answer:
SA = 1244.64 square centimeters
Step-by-step explanation:
From the attached figure
The formula of the surface area of the prism is SA = 2B + PH, where
- B is the area of its base
- P is the perimeter of its base
- H is the distance between its bases
The base of the prism is a regular hexagon with side 8 cm
If you join each vertex of the hexagon with its center you will form 6 congruent triangles with base 8 cm and height 6.93 cm
The area of the hexagon = 6 × area of a triangle
∵ The base of the triangle = 8 cm
∵ Its height = 6.93 cm
- The formula of the area of a triangle is A =
× base × height
∴ Area of the triangle =
× 8 × 6.93 = 27.72 cm²
- Lets find the area of the hexagon
∴ The area of the hexagon = 6 × 27 .72 = 166.32 cm²
∴ B = 166.32 cm²
The formula of the perimeter of the regular hexagon is P = 6 × s, where s is the length of its side
∵ The side of the hexagon is 8 cm
∴ P = 6 × 8
∴ P = 48 cm
∵ The distance between the two bases is 19 cm
∴ H = 19 cm
Substitute the values of B, P and H in the formula of the surface area above
∵ SA = 2(166.32) + (48)(19)
∴ SA = 332.64 + 912
∴ SA = 1244.64 square centimeters
Answer:
The system of equations is:
x + y = 42
4x + 2y = 120
And there are 24 chickens.
Step-by-step explanation:
We know that the total number of cows (x) plus the total number of chickens (y) is 42, because Farmer Brown has 42 animals.
We also know that cows (x) have 4 legs and so 4 times the number of cows is the number of cow legs. And chickens (y) have 2 legs, so the number of chickens times two represents the total chicken legs. The sum of 4x + 2y is 120 because there are 120 legs in total.
To solve the system of equations, first solve each equation for y.
In the first equation:
x + y = 42
Subtract x from both sides to isolate y.
y = 42 - x
Second equation:
4x + 2y = 120
Subtract 4x from both sides
2y = 120 - 4x
Divide both sides by 2
y = 60 - 2x
Now that the y's are isolated in both equation, you can put them into 1 equation. Where y = y:
y = 42 - x
y = 60 - 2x
42 - x = 60 - 2x
Add 2x to both sides
42 + x = 60
Subtract 42 from both sides
x = 18
Since x is the number of cows, we know that Farmer Brown has 18 cows.
Now we can substitute the x value into one of the equations:
y = 42 - x
y = 42 - (18)
y = 24
The number of chickens is represented by y, so there are 24 chickens.