Answer:
option A and B

and

Step-by-step explanation:
we have

The formula to solve a quadratic equation of the form
is equal to

in this problem we have

so

substitute in the formula


so

and

So 30/48=15/(x+9)
this could be easily solved by recognizing the proportion (the other way is usiing full algebra and doing multiply both sides by 48(x+9) and then divide both sides by 30 then subtract 9)
30 is 2 times of 15
therefor 48 is 2 times of (x+9)
48=2 times (x+9)
divide both sides by 2
24=x+9
subtract 9
15=x
x=15
It's diameter is 17.98. (I'm pretty sure I'm right I even used a calculator, if not sorry)
This equation is NEVER true. Let's solve the equations algebraically by applying the Distributive Property of Multiplication and transposing the terms across the equality sign. The solution is as follows:
<span>2(5x+4)=10x+6
10x + 8 = 10x + 6
10x - 10x = 6 - 8
0 = -2
Therefore, it is not true.</span>