HELP brainliest will be given

volume of cylinder

= area of circle × height

= πr² × h

= (22/7 × 9²) × 20

= 254.57 × 20

= 5091.4 cm³

5089.4 cm³

Step-by-step explanation:

The volume (V) of a cylinder is calculated as

V = Ah ( A is the area of the base and h the height ), thus

V = πr²h

   = π × 9² × 20 = π × 81 × 20 = 1620π ≈ 5089.4 cm³ ( to 1 dec. place )

u = -(6/7)w

step-by-step explanation:

place all values with 'u' on one side of the equation.

4u + 8w = - 3u + 2w

4u + 3u = 2w - 8w

further simplify the equation by solving the addition and subtraction.

7u = - 6w

make 'u' the independent variable by placing its co-efficient on the right-hand side.

u = - (6/7)w