For this case we must indicate which of the equations shown can be solved using the quadratic formula.
By definition, the quadratic formula is applied to equations of the second degree, of the form:

Option A:

Rewriting we have:

This equation can be solved using the quadratic formula
Option B:

Rewriting we have:

It can not be solved with the quadratic formula.
Option C:

Rewriting we have:

This equation can be solved using the quadratic formula
Option D:

Rewriting we have:

It can not be solved with the quadratic formula.
Answer:
A and C
Hi there!
Let the first number be represented by X.
The second number (which is 2 more than four times the other), can be represented by 4X + 2.
We can now find the sum of this expression.
X + 4X + 2
Collect terms
5X + 2
The sum of the numbers is 18. Therefore we can set up the following equation.
5X + 2 = 18
Subtract 2.
5X = 16
Divide both sides by 5.
X = 16/5 = 3 1/5.
Therefore, the first number is 3 1/5. To find the second number we must plug in X = 3 1/5 into the expression 4X + 2
4 * (3 1/5) + 2 = 12 4/5 + 2 = 14 4/5
The two numbers are

~ Hope this helps you!
Answer:
14/16
Step-by-step explanation:
If you multiply 8 by 2 you get 16 so multiply 7 by 2 and you get 14/16