Intermediate Algebra (11th edition)

Theoretically, a system of this type can be solved by graphing. However, the graph of a linear equation with three variables is ...

OBJECTIVE 2 Solve linear systems (with three equations and three vari- ables) by elimination.Since graphing to find the solution ...

Solving a System in Three Variables Solve the system. (1) (2) (3) Step 1 Since zin equation (1) has coefficient 1, we choose zas ...

Step 6 It appears that the ordered triple is the only solution of the system. We must check that the solution satisfies all thre ...

NOW TRY We can find yby substituting for zin equation (2). (2) Let Add 6. or Divide by 8; lowest terms Check to verify that the ...

SECTION 4.2 Systems of Linear Equations in Three Variables 231 Solving Another Special System Solve the system. (1) (2) (3) Mult ...

Solve each system of equations. See Example 2. 232 CHAPTER 4 Systems of Linear Equations 15. 1 2 x+ 3 2 y+ 3 4 z= 21 - 3 4 x- 1 ...

Brain Busters Extend the method of this section to solve each system. Express the solution in the form 1 x, y, z, w 2. SECTION 4 ...

OBJECTIVE 1 Solve geometry problems by using two variables. Finding the Dimensions of a Soccer Field A rectangular soccer field ...

Step 4 Solvethe system of equations. Since equation (2), is solved for L, we can substitute for Lin equation (1) and solve for W ...

Step 4 Solvethe system. To eliminate h, multiply equation (2), by and add. (1) Multiply each side of (2) by. Add. Divide by. To ...

Step 3 Write a system of equations.When the xounces of 5% solution and the younces of 20% solution are combined, the total numbe ...

Step 3 Write a system of equations.The car travels 8 km per hr faster than the truck. Since the two rates are xand y, (1) Both v ...

Solving a Problem Involving Prices At Panera Bread, a loaf of honey wheat bread costs $2.95, a loaf of sunflower bread costs $2. ...

Solving a Business Production Problem A company produces three flat screen television sets: models X, Y, and Z. Each model X se ...

3.Venus and Serena measured a tennis court and found that it was 42 ft longer than it was wide and had a perimeter of 228 ft. Wh ...

242 CHAPTER 4 Systems of Linear Equations 10.In 2009, the FCI prices for Major League Baseball and the National Football League ...

Concept Check The formula (distance rate time) is used in the applications in Exercises 27–30.To prepare to use this formula, wo ...

Solve each problem by using two variables. See Examples 1 – 4. 244 CHAPTER 4 Systems of Linear Equations rtd Upstream 2 Downstre ...

39.In a certain triangle, the measure of the second angle is greater than three times the first. The third angle measure is equa ...