Question

What is 15 = -y + 10

Answer 1

It's a simple linear equation in a single variable, 'y' .  Its solution is the number
that 'y' must be in order to make the equation a true statement.  Here's how to
find the solution:

Write the equation:    15 = -y + 10

Subtract 10 from each side:    5 = -y

Multiply each side by -1 :      -5 = y

Answer 2

15=-y+10
=-10+15=-y
=5=-y
=-5=y
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