Mario's mistake is made when doing reciprocal.
7 / (2/3) =
I cannot divide by 2/3, but if I do reciprocal, I can multiply by 3/2. The seven comes first, so it should not be flipped.
Mario's mistake was when he flipped the 7 (or 7/1) to 1/7.
Answer:
x = all real numbers
Step-by-step explanation:
first you need to solve the first equation to figure out what y is.
4x - y = 2
<em>add y to both sides of the equation</em>
4x = 2 + y
s<em>ubtract 2 from both sides of the equation</em>
4x - 2 = y
now that you know what y is, you can substitute it in the next equation.
3y = 12x - 6
3(4x - 2) = 12x - 6
<em>open the parenthesis </em>
12x - 6 = 12x - 6
<em>subtract 12x from both sides of the equation</em>
-6 = -6
regardless of what x is, -6 will always equal -6.
so, the answer is all real numbers.