Answer: 
Step-by-step explanation:
To solve the exercise you must apply the following proccedure:
- Apply the distributive property.
- Keep on mind that when you multiply two powers with equal base, you must add the exponents.
- Add like terms.
Therefore, you obtain the following product:

AC is a common side, ∠ACD = ∠ACB and CD = BC ⇒ ΔACD and ΔABC <span>are congruent (SAS definition).
</span>Congruent triangles have exactly the same three angles, so ∠D = ∠B.<span>
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Answer:
This can be because our number, 300,684, has only four digits different than zero.
Then we can write this number as:
300,684 = 300,000 + 600 + 80 + 4.
So we add only 4 terms.
So when we write a number in this form, we will have the same numbers of terms in the addition that the number of digits different than zero in our original number.
To express the volume of both trucks in a single expression, we add the expressions,
8x² + 2x - 1
and also,
7x² - 2x + 1
Adding the corresponding terms in the expressions will give us an answer of,
15x²
Thus, the volumes of the trucks in a single expression is 15x².