For this case we have the following equation:

Step 1 of the solution is to make the distributive property.
We have then:

Step 1 is correct.
The step is to combine similar terms. Caleb wrote:

He wrongly combined the similar terms on the right side of the equation.
The correct solution is:
Answer: In step 2, the like terms were not combined on the right side of the equation.
Answer:
Step-by-step explanation:
a) ΔACD ~ ΔABE so the ratios of corresponding sides are the same. That is ...
CD/BE = CA/BA
CD/3.8 = 12.3/8.2
CD = 3.8×12.3/8.2 = 5.7 . . . . cm
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b) As above, the ratios of corresponding sides are the same.
ED/AD = BC/AC
ED/9.15 = (12.3-8.2)/12.3 . . . . BC = AC - AB
ED = 9.15×4.1/12.3 = 3.05 . . . . cm
They are both correct in their computation
(28.5-28.5(.3))+.1(28.5-28.5(.3))=$21.945
28.5(.7)(1.1)=$21.945
And since they each have $22 to spend, they have enough to purchase the book.