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4 votes
Solve for y in the equation 4y+15=-5y+9
a)-6
b) -2/3
c)2/3
d)6

User Tillz
by
6.5k points

2 Answers

0 votes
Your goal is to isolate y

To begin isolating y, perform the opposite operation by subtracting 15 on both sides of the equation

4y = -5y - 6

Perform the opposite operation by adding 5y on both sides of the equation

9y = -6

Perform the opposite operation by dividing both sides of the equation by 9

y=
y= -(1)/(3)
User NonNumeric
by
7.0k points
3 votes
First off, you need to have your ys on the same side. Here's how to do it:
4y + 15 = -5y + 9
4y + 5y = 9 - 15 (once a number goes to the other side, it changes its sign)
9y = -6
y = -6/9
y = -2/3

The correct answer is B. -2/3
User Ikida
by
7.4k points