Grace gives her sister a riddle: i have number x. i add 15 to twice x to get result a. i subtract 4 from x to get result b. i multiply result b by 3 to get result c. result a is equal to result c. grace's sister said the riddle cannot be solved, but grace thought otherwise. who is right? explain

Let's follow step by step.

15 + 2x = A

x - 4 = B

3b = C

A=C

I'm not sure who is right, but I hope this clears up the air

<3

infinitely many solutions

step-by-step explanation:

we have been given the equation;

2(2x + 3) = -4 + 2(2x + 5)

we need to determine the value of x.

2(2x + 3), we expand this expression to obtain 4x + 6

similarly 2(2x + 5) will become 4x + 10

now we have;

4x + 6 = -4 + 4x + 10

4x + 6 = 4x + 10 - 4

4x + 6 = 4x + 6

the expression on the left hand side is identical to the one on the right hand side. therefore, we are looking at just a single straight line whose equation is;

y = 4x + 6

consequently, we shall have infinitely many solutions

the correct is answer is a 9-sided polygon!