91Ó°ÊÓ

Question: Patterns The table shows sums of odd numbers.

a. Copy and complete the table. Identify any pattern that you see.

b. Write a variable expression for the sum of the first n odd numbers.

c. Use your expression from part (b) to find the sum of the first 100 odd numbers

Error Analysis Describe and correct the error in writing a variable expression for the difference of a number and 31.

Plot the point in a coordinate plane. Describe the location of the point.

Find the product or quotient)

– 4 (– 8)

Music Competition The double bar graph shows three students’ scores in a music competition. A student’s final score is the sum of the points for technique t and for interpretation i.

a. Write a variable expression for a student’s final score.

b. Find each student’s final score.

c. Interpret You earn 35 points for technique. At least how many points must you earn for interpretation to have a higher score than students A, B, and C?

State the opposite of the number.

$81$

Your checking account shows an overdraft, or a negative balance. Your present balance is – \(25. You deposit \)108, then withdraw $20 at an ATM. Explain why the expression – 25 + 108 + (– 20) represents your new balance. Do you expect the new balance to be positive or negative? Explain.

Find the product or quotient

5.2 ÷ 1.25

Evaluate the experssion when $a=2.5, b=15,\text{and}c=3.5$

localid="1648024266631" $bc$

Evaluate the expression when $x=-8$.

localid="1649144256707" $-x$