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3x+4y=-30 2x-5y=72 find y

2 Answers

3 votes

nvm sorry wrong answer

User Mbogh
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6.9k points
5 votes

Answer:-12

Explanation:

To solve for y, we can use the second equation to isolate x and substitute the result into the first equation:

2x - 5y = 72

2x = 5y + 72

x = (5y + 72)/2

Now we can substitute this expression for x into the first equation:

3x + 4y = -30

3((5y + 72)/2) + 4y = -30

Simplifying the left side:

(15/2)y + 108 + 4y = -30

Combining like terms:

(23/2)y = -138

Dividing both sides by (23/2):

y = -138 * 2/23

Simplifying:

y = -12

Therefore, the value of y that satisfies both equations is -12.

User Rodrigo Ribeiro
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8.1k points