Final answer:
To solve the system of equations, substitute y = 2x into the second equation 2x + 3y = 16, combine like terms to get 8x = 16, and then divide both sides by 8 to find x = 2. The correct choice is D. 8x = 16.
Step-by-step explanation:
The student has asked how to substitute the first equation for y in the second equation and then combine like terms. The original equations are:
y = 2x
2x + 3y = 16
First, we substitute the expression for y from the first equation into the second equation:
2x + 3(2x) = 16
This simplifies to:
2x + 6x = 16
Combining like terms (the terms with x), we get:
8x = 16
This can be further simplified by dividing both sides of the equation by 8, giving us:
x = 2
The option that shows the result of the substitution and the combination of like terms is:
D. 8x = 16