Answer: it’s A
Step-by-step explanation:
1. 15x
2. 21
3. 4
You’re welcome
<u>answer:</u> 
<u>work:</u>
| subtract 5x and move it over to the 7x, and solve
| subtract 4 and move it over to the 10, and solve
| divide by 2
| final answer
hope this helps! ❤ from peachimin
A) (3)² = 3 × 3 and 10(8)² = 10 × 8 × 8
B) (3)² = 9 and 10(8)² = 640
For any number x, the square of the number denoted by (x)² is equal to 2 times x multiplied by itself or x*x.
Here, we are given two expressions- (3)² and 10(8)²
we need to write both of them in expanded form and then write their values.
Expanded form of (3)² is 3 × 3
The value of the expression (3)² will be-
(3)² = 3 × 3 = 9
Similarly, expanded form of 10(8)² is 10 × 8 × 8
The value of the expression 10(8)² will be-
10(8)² = 10 × 8 × 8 = 640
Learn more about expanded form here-
https://brainly.in/question/19612773
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