A equation for the ninth term of a arithmetic sequence who seventh term is 21 and common difference of 5

Step-by-step explanation:

From the question we are told that:

Seventh term

Common difference

Generally Equation for seventh term

Therefore the  First Term is given as

Generally the equation for 9th term is mathematically given by

14

step-by-step explanation:

34.5 cm

step-by-step explanation:

generally for a circular segment of angle, θ° and radius r

arc length

= (θ/360) x circumference

= (θ/360) x 2πr

in our case, θ = 60°, π=3.142 and r = 33 cm

substitute into above formula

arc length

= (60/360) x 2(3.142)( 33) = 34.5 cm