Date ______

Lesson 10-7: Using systems of equations to solve verbal problemsp.426 - 431

REVIEW

Slope Formula

Slope-Intercept Form ___ = ______+ ___

Standard Form of a Linear Equation __ __ + __ __ = ___

Parallel Lines - ______

Perpendicular Lines - ______

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Steps for verbal problems.

1. Use two different variables to represent the unknowns. Write 2 “let” statements.

2. Use formulas or information given to write a system of equations using your two variables above.

3. Solve the system of equations by substitution or elimination.

4. Solve for the second variable.

5. Check to see if your answer makes sense.

Ex 1|The sum of two numbers is 36. Their difference is 24. Find the numbers.

1. Use two different variables to represent the unknowns.

Let

Let

2. Use formulas or information given to write a system of equations using your two variables above.

3. Solve the system of equations by substitution or elimination.

4. Solve for the second variable.

5. Check to see if your answer makes sense.

Ex 2| The sum of two numbers is 900. When 4% of the larger number is added to 7% of the smaller number, the sum is 48. Find the numbers.

1. Use two different variables to represent the unknowns.

2. Use formulas or information given to write a system of equations using your two variables above.

3. Solve the system of equations by substitution or elimination.

4. Solve for the second variable.

5. Check to see if your answer makes sense.

Ex 3|Two angles are supplementary. The larger angle measures 15o less than twice the smaller. Find the degree measure of each angle.

1. Use two different variables to represent the unknowns.

2. Use formulas or information given to write a system of equations using your two variables above.

3. Solve the system of equations by substitution or elimination.

4. Solve for the second variable.

5. Check to see if your answer makes sense.

Ex 4| The owner of a men’s clothing store bought six belts and eight hats for $140. A week later, at the same prices, he bought nine belts and six hats for $132. Find the price of a belt and the price of a hat.

1. Use two different variables to represent the unknowns.

2. Use formulas or information given to write a system of equations using your two variables above.

3. Solve the system of equations by substitution or elimination.

4. Solve for the second variable.

5. Check to see if your answer makes sense.

Ex 5| When Angelo cashed a check for $170, the bank teller gave him 12 bills, some $20 bills and the rest $10 bills. How many bills of each denomination did Angelo receive?

1. Use two different variables to represent the unknowns.

2. Use formulas or information given to write a system of equations using your two variables above.

3. Solve the system of equations by substitution or elimination.

4. Solve for the second variable.

5. Check to see if your answer makes sense.

HW: p.429/3-314’s

Guided notes 10-7, pg.1