First, subtract 2y from both sides:
2y - 7 - 2y = 3y + 4 - 2y, so -7 = y + 4.
Next, subtract 4 from both sides:
-7 - 4 = y + 4 - 4, so y = -11.
Add 3 to both sides of the equation:
4x - 3 + 3 = 9 + 3, so 4x = 12.
Now, divide both sides by 4:
4x ÷ 4 = 12 ÷ 4, so x = 3.
To solve x² - 4 = 0, add 4 to both sides: x² = 4.
Now, take the square root of both sides:
x = ±√4, so x = ±2.
To solve for x, subtract 5 from both sides of the equation:
2x + 5 - 5 = 15 - 5, so 2x = 10.
Now, divide both sides by 2:
2x ÷ 2 = 10 ÷ 2, so x = 5.
Combine like terms:
3x + 4x = 7x, so the simplified expression is 7x - 5.
