Section 3.1 Solving Equations Introduction
- Convert 9/25 to a percentage.
- A football team played 27 games and won ¾ of the games. How many games did they lose?
- If 2.5 pounds of apples cost $2.35 at Kroger and 3 pounds of apple cost $2.70 at Wal-Mart, which store offers the best deal per pound?
A little background information:
- Two soccer teams are tied at half time: 2 to 2
- If each team scores 3 goals in the next half, the score will now be tied.
- Addition Property of Equality
- If the same number is added to equal numbers, the sums are equal.
A little more background info….
- Two sporting goods store charge $36 for a soccer ball.
- If during a spring sale, each store reduces the price by $5, both stores will be charging the same price.
- If the same number is subtracted from equal numbers, the differences are equal.
- The same holds true for multiplication and division.
The Keys to Solving Equations
- Use the Properties of Equality
- “ Whatever you do to one side of the equal sign, do the same thing to the opposite side of the equal sign.”
- Ex: If you multiply by -1 on the left side, then you must multiply by -1 on the right side.
- Use the opposite operation to solve equations.
- The opposite of addition is _______________.
- The opposite of subtraction is _______________.
- The opposite of multiplication is _______________.
- The opposite of division is _________________.
subtraction addition multiplication division
- MOST IMPORTANTLY, SHOW ALL OF YOUR WORK!
Practice with One-Step
Practice with Two-Step 7.) 5x + 4 = 29 8.)
Practice with Distributive Property
- We use the distributive property to eliminate the parentheses (or groupings).
- 9.) 2(2x + 6) = 20 10.) 6(x-3) = 24
Practice combining like terms
- 11.) 2x + 6x = 30 12.) 7x + 8 – 3x = 32
Solving Equations Relay
- Worksheet: Solving Basic Equations (page 21)