Question 413185
4(5x + 4) - 9 = 20x + 7
20x + 16 - 9 = 20x + 7 {used distributive property}
20x + 7 = 20x + 7 {combined like terms}
0 = 0 {subtracted 20x and 7 from both sides}
= infinite solutions


Note:
- When the variable disappears and you get a statement 
that is always true, then there are infinite solutions.

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