Question

If r + 9 = 42, does r + 9 – 9 = 42 +9?

Why why not? I forgot to put spaces last time, and there's no negative numbers

Answer 1

Answer: No, but you're close

Start with r + 9 = 42.

Then we subtract 9 from both sides. This will get rid of the +9 and isolate r.

The r+9 on the left becomes r+9-9 like you wrote. But the 42+9 on the right hand side is not correct. It should be 42-9

Here are the steps to isolate r.

r + 9 = 42

r + 9 - 9 = 42 - 9 .... subtracting 9 from both sides

r + 0 = 33

r = 33

As a check,

r + 9 = 42

33 + 9 = 42

42 = 42

This confirms that r = 33 is the correct solution.

Answer 2

While r + 9 = 42, the expression r + 9 - 9 simplifies to r, which equals 42 when r + 9. Therefore, r + 9 - 9 does not equal 42 + 9 but just equals 42.

Step-by-step explanation:

The question asks whether the expression r + 9 - 9 equals 42 + 9 given that r + 9 = 42. Using basic rules of algebra, we know that adding and then subtracting the same number (in this case, 9) from a variable will leave the variable unchanged. Thus, r + 9 - 9 simplifies to just r. Since it was given that r + 9 = 42, we know that r must equal 42 - 9. Subtracting 9 from both sides of the original equation does not logically lead to adding 9 to the 42, as these operations are not equivalent. Therefore, r + 9 - 9 does not equal 42 + 9; rather, r + 9 - 9 equals 42, which is the original value given for r + 9.