Solve the inequality 5x - 7 > 2x +5

What does this inequality sign mean? That A "is greater than" B.

We can treat inequalities as if they are = signs as long as we don't multiply or divide by negative numbers. What would happen then? The sign would swap around - we can see this with an example of 5 > 3 but -5 < -3.

Now its important to get all the unknowns (x's) on one side. Do this by repeating the same action on both sides. To get rid of the 2x on the RHS you have to take away 2x from both the LHS and RHS....  5x - 7 - 2x > 5

Repeat to get rid of anything thats not an x on the LHS by adding 7 to both.... 5x - 2x > 5 + 7

By simplifying we get: 3x > 12.... then divide both sides by 3 to get.... x > 4

CC

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