The correct answer is "He did not distribute correctly". The correct incomplete-worked expression is x - 10 + 4x = 10
I hope this helps!
Answer:

Step-by-step explanation:
The distributive law states that

The expression 3+21a+15b consists of three terms:
- 3=3·1;
- 21a=3·7a;
- 15b=3·5b.
You can see that 3 is the common factor of these three terms, thus

Hello here is a solution :
equation for the line is : y = ax+b a : slope
a = 0
passes through the point (-5, 4) : 4 =0(-5)+b
b= 4
equation for the line is : y =4
Answer: Third Choice. x= 6 1/3
Step-by-step explanation:
Given
f(x) = 9x² - 54x - 19
Completing the square
3x -19
3x 1
Substitute back to the function
f(x) = (3x-19) (3x+1)
Simplify
x= 6 1/3 or -1/3
Hope this helps!! :)
Please let me know if you have any questions