25 —y =12
you put 25 on the other side of the equal sign and it becomes -y = 12 - 25
and solve for y (you have make y positive)
I do not understand
add y to both sides
25 - y + y = 12 + y
which is just 25 = 12+y
Now subtract 12 from both sides
25-12 = 12+y-12
which is just 13 = y
done!
If two things are equal, then if you change each the same way, they stay equal.
To solve the equation 25 - y = 12, we can follow these steps:
Step 1: Begin with the given equation: 25 - y = 12.
Step 2: We want to isolate the variable y on one side of the equation. To do this, we can move the constant term (12) to the other side of the equation by performing the opposite operation. Since 12 is added to 25, we can subtract 12 from both sides:
25 - y - 12 = 12 - 12.
Simplifying this, we get: 25 - 12 - y = 0 - y = 0.
Step 3: At this point, our equation becomes 25 - 12 - y = 0. Simplifying further, we find: 13 - y = 0.
Step 4: Next, isolate the variable by subtracting 13 from both sides of the equation:
13 - y - 13 = 0 - 13.
Simplifying this, we get: -y = -13.
Step 5: Finally, multiply both sides of the equation by -1 to solve for y:
-1 * -y = -1 * -13.
Simplifying this, we find: y = 13.
So, the solution to the equation 25 - y = 12 is y = 13.