PLEASE HELP!!!!!! WILL MARK BRAINIEST FOR BEST ANSWER!!!!!!
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2a + 7b = 0 ⇒ 10a + 35b = 0
3a - 5b = 31 ⇒ 21a - 35b = 217
31a = 217
a = 7
2a + 7b = 0
2(7) + 7b = 0
14 + 7b = 0
7b = -14
b = -2
(x, y) = (7, -2)
1. Associative Property of Addition
2. Addition Property of Equality
3. Division Property of Equality
4. Substitution Property of Equality
5. Multiplication Property of Equality
6. Subtraction Property of Equality
7. Simplify