Exam 9: Equations, Inequalities, and Problem Solving

Write the algebraic expression described. -The sum of the angles of a triangle is 180°. If one angle of a triangle measures x° and a second angle measures (4x + 20)°, express the measure of the third angle in terms of x.

Solve the equation. -5(2x - 1)= 20

Write the algebraic expression described. -If x represents the first of three consecutive even integers, express the sum of the three integers in terms of x.

Solve. Round to the nearest hundredth, if necessary. -10% of what number is 60?

Solve the equation. -7(x + 4)= (7x + 28)

Substitute the given values into the formula and solve for the unknown variable. -P = 2L + 2W; P = 18, W = 6

Solve the equation. - $\frac { 1 } { 5 } x$ x = 6

Solve. -A certain store has a fax machine available for use by its customers. The store charges $1.60 to send the first page and $0.45 for each subsequent page. Use an inequality to find the maximum number of pages that can be Faxed for $6.55

Write the algebraic expression described. Simplify if possible. -Two numbers have a sum of 28. If one number is q, express the other number in terms of q.

Solve. Round answers to the nearest cent. -A store is advertising 45% off sale on everything in the store. Find the discount of a fax machine that regularly sells for $170.

Solve the problem. -There are 22 more sophomores than juniors in an 8 AM algebra class. If there are 60 students in this class, find the number of sophomores and the number of juniors in the class.

Solve the inequality. - $20 x + 45 > 5 ( 3 x + 18 )$

Solve the inequality. - $\frac { x } { 7 } > 3$

Substitute the given values into the formula and solve for the unknown variable. -I = prt; I = 60, p = 250, r = 0.08

Solve the equation. - $\frac { 3 } { 2 } x + \frac { 1 } { 5 } = \frac { 7 } { 5 } x$

Solve. Round to the nearest hundredth, if necessary. -3.1 is what percent of 23.6?

Solve the equation. -3r + 4 = 34

Solve the inequality. - $7 x \leq 91$

Solve the equation. --0.3(x - 9)+ x = 0.5(3 - x)

Solve. -The owners of a candy store want to sell, for $6 per pound, a mixture of chocolate-covered raisins, which usually sells for $3 per pound, and chocolate-covered macadamia nuts, which usually sells for $8 per pound. They have a 40-pound barrel of the raisins. How many pounds of the nuts should they mix with the barrel of Raisins so that they hit their target value of $6 per pound for the mixture?