Solve the inequality for x:
5x - 3 ≤ 7x +7
Subtract 7x from each side:
-2x -3 ≤ 7
Add 3 to each side:
-2x ≤ 10
Divide both sides by -2, also when dividing both sides of an inequality you flip the direction of the inequality sign:
x ≥ -5
The dot will be on -5, because the inequality includes equal to, the dot is solid and is greater than, the arrow will point to the right.
The correct answer is D.
The perimeter of each is the sum of the lengths of its sides.
Triangle Perimeter = 16 + 4x-3 +3x = 7x+13
Square Perimeter = 2x +2x +2x +2x = 8x
If these are equal, you have

The length of a side of the square is 26 units.
I would try Khan Academy. He does very good explainations
The answer is 16 ft because 6 ft tall over 4 feet 6 inches (4.5) is equal to x (tree's height) over 12 ft. You cross multiple and get 72 = 4.5x then you take 72 and divide by 4.5 to get the tree's height
