​If you have an original value of x and the value of that increases then the coefficient attached to the x to represent the situation would be greater than 1.

Example: ​Last year the class population was p. This year the class population is 1.15p.

• ​This means that the population increased by 15% because 1.15 as a percent would be 115%, which is 15% more than the original.

Example: Last year the class population was p. This year the class population is .65p.

• This means that the population decreased by 35% because .65 as a percent would be 65%, which is 35% less than the original.​

What is perimeter?

Perimeter is the measurement around the surface of an object. If you wanted to find the perimeter of a;

• square - multiply one side by 4, or add the side up 4 times

  • ex) One side of a square is 2x - 5, so the perimeter is 4(2x-5) or 2x - 5 + 2x - 5 + 1x - 5 + 2x - 5... Both reduce to 8x - 20.

• rectangle - has two congruent sides. So multiply each dimension by 2 and then add them up, or add all 4 sides.

  • ex) If the length of a rectangle is 3w + 1 and the width is w + 2 then the perimeter is 2(3w +1) + 2(w + 2) or 3w+1 + 3w+1 + w+2 + w+2.... both reduce to 8w + 6.

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