The following is a linear sequence. 1, 4, 7, 10, using the explicit formula 3n - 2 find the 90th term in the sequence. a. 90b. 270c. 268d. 265

We have

We're asked for

C 268

5=812a+9+3

step 1: simplify both sides of the equation.

5=812a+9+3

5=(812a)+(9+3)(combine like terms)

5=812a+12

5=812a+12

step 2: flip the equation.

812a+12=5

step 3: subtract 12 from both sides.

812a+12−12=5−12

812a=−7

step 4: divide both sides by 812.

812a /812 = -7/812

a= -1/116

so the answer is

a=   -1/116