1. Example 2
Multiple Choice Practice 2 3 6 4
A zoo currently spends $1580 to feed its American flamingos. Next year its budget for feeding the flamingos will be $2370, and it will cost $395 to feed each additional flamingo the zoo buys. How many new flamingos can the zoo buy next year?
Write and solve a two-step equation to find the number of flamingos. Write a verbal model. Let n be the number of additional flamingos.
SOLUTION

2. Example 2
Multiple Choice Practice
2370
395n =
1580 +
Write an algebraic model.
2370
1580 –
395n = +
Subtract 1580 from each side.
790
395n =
Simplify.
395
790
395n =
Divide each side by 395. 2 n =
Simplify. 2

3. The zoo can buy 2 new flamingos next year.
Example 2
Multiple Choice Practice
The zoo can buy 2 new flamingos next year.
ANSWER
The correct answer is A. 3

4. Example 3 Solve 8. 14 = 2 x – 14 2 x – 8 = 14 2 x – + 8 = 2 x 22 = 2 •
Solving with a Variable in the Numerator
Solve 8. 14 = 2 x – 14 2 x – 8 =
Write original equation. 14 2 x – + 8 =
Add 14 to each side. (Addition property of equality) 2 x 22 =
Simplify. 2 • x 22 =
Multiply each side by 2. (Multiplication property of equality) x 44 =
Simplify.

5. Example 3 ANSWER The solution is 44.
Solving with a Variable in the Numerator
ANSWER
The solution is 44.

6. Example 4 Solve 5 = 7 8x. – 7 5 = 8x – 5 7 – = 8x 2 = 8x – 2 8 – = 8x
Solving with a Negative Coefficient
Solve 5 = 7
8x. –
Write original equation. 7 5 = 8x –
Subtract 5 from each side.
(Subtraction property of equality) 5 7 – = 8x
Simplify. 2 = 8x – 2 8 – = 8x
Divide each side by 8.
(Division property of equality)
Simplify. x = 1 4 –

7. new tortoise costs $575 to feed. A zoo’s budget for
Guided Practice
for Examples 2, 3, and 4
2. FEEDING COSTS It costs a zoo $1150 this year to feed tortoises. Each
new tortoise costs $575 to feed. A zoo’s budget for
tortoise food next year is $2875. How many new
tortoises can the zoo buy next year?
ANSWER
3 tortoises
Solve the equation. Check your solution. 11 = 3 y 13 + 3.
ANSWER 6

8. Solve the equation. Check your solution.
Guided Practice
for Examples 2, 3, and 4
Solve the equation. Check your solution. 4. 3 – 4 = 5 z
ANSWER 35 5 23 = + 6x – 5.
ANSWER 3 – 6 16 = a – 6.
ANSWER 10